137209428 has 18 divisors (see below), whose sum is σ = 346835034. Its totient is φ = 45736464.

The previous prime is 137209427. The next prime is 137209433. The reversal of 137209428 is 824902731.

137209428 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 130919364 + 6290064 = 11442^2 + 2508^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (36), and also a Moran number because the ratio is a prime number: 3811373 = 137209428 / (1 + 3 + 7 + 2 + 0 + 9 + 4 + 2 + 8).

It is a junction number, because it is equal to n+sod(n) for n = 137209392 and 137209401.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (137209427) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1905651 + ... + 1905722.

It is an arithmetic number, because the mean of its divisors is an integer number (19268613).

Almost surely, 2^137209428 is an apocalyptic number.

137209428 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

137209428 is an abundant number, since it is smaller than the sum of its proper divisors (209625606).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

137209428 is a wasteful number, since it uses less digits than its factorization.

137209428 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3811383 (or 3811378 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 36.

The square root of 137209428 is about 11713.6428151109. The cubic root of 137209428 is about 515.7762235013.

The spelling of 137209428 in words is "one hundred thirty-seven million, two hundred nine thousand, four hundred twenty-eight".