137428728 has 32 divisors (see below), whose sum is σ = 343982160. Its totient is φ = 45754880.

The previous prime is 137428721. The next prime is 137428741. The reversal of 137428728 is 827824731.

It is a Cunningham number, because it is equal to 11723²-1.

It is a self number, because there is not a number n which added to its sum of digits gives 137428728.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (137428721) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 20518 + ... + 26378.

Almost surely, 2^137428728 is an apocalyptic number.

It is an amenable number.

137428728 is an abundant number, since it is smaller than the sum of its proper divisors (206553432).

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

137428728 is a wasteful number, since it uses less digits than its factorization.

137428728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6847 (or 6843 counting only the distinct ones).

The product of its digits is 150528, while the sum is 42.

The square root of 137428728 is about 11722.9999573488. Note that the first 4 decimals coincide. The cubic root of 137428728 is about 516.0508633234.

The spelling of 137428728 in words is "one hundred thirty-seven million, four hundred twenty-eight thousand, seven hundred twenty-eight".