137721924 has 24 divisors (see below), whose sum is σ = 357057120. Its totient is φ = 45907272.

The previous prime is 137721923. The next prime is 137721971. The reversal of 137721924 is 429127731.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (137721923) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 637494 + ... + 637709.

It is an arithmetic number, because the mean of its divisors is an integer number (14877380).

Almost surely, 2^137721924 is an apocalyptic number.

It is an amenable number.

137721924 is an abundant number, since it is smaller than the sum of its proper divisors (219335196).

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

137721924 is a wasteful number, since it uses less digits than its factorization.

137721924 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1275216 (or 1275208 counting only the distinct ones).

The product of its digits is 21168, while the sum is 36.

The square root of 137721924 is about 11735.4984555408. The cubic root of 137721924 is about 516.4175905695.

The spelling of 137721924 in words is "one hundred thirty-seven million, seven hundred twenty-one thousand, nine hundred twenty-four".