137617921 has 24 divisors (see below), whose sum is σ = 164670720. Its totient is φ = 114633792.

The previous prime is 137617919. The next prime is 137617939. The reversal of 137617921 is 129716731.

It is not a de Polignac number, because 137617921 - 2¹ = 137617919 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (137617121) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 282340 + ... + 282826.

It is an arithmetic number, because the mean of its divisors is an integer number (6861280).

Almost surely, 2^137617921 is an apocalyptic number.

It is an amenable number.

137617921 is a deficient number, since it is larger than the sum of its proper divisors (27052799).

137617921 is an equidigital number, since it uses as much as digits as its factorization.

137617921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 653 (or 646 counting only the distinct ones).

The product of its digits is 15876, while the sum is 37.

The square root of 137617921 is about 11731.0664903068. The cubic root of 137617921 is about 516.2875640578.

The spelling of 137617921 in words is "one hundred thirty-seven million, six hundred seventeen thousand, nine hundred twenty-one".