137521657 has 8 divisors (see below), whose sum is σ = 169257536. Its totient is φ = 108808272.

The previous prime is 137521609. The next prime is 137521663. The reversal of 137521657 is 756125731.

137521657 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 137521657 - 2⁷ = 137521529 is a prime.

It is a super-2 number, since 2×137521657² = 37824412288051298, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (137521607) 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, 755523 + ... + 755704.

It is an arithmetic number, because the mean of its divisors is an integer number (21157192).

Almost surely, 2^137521657 is an apocalyptic number.

It is an amenable number.

137521657 is a deficient number, since it is larger than the sum of its proper divisors (31735879).

137521657 is a wasteful number, since it uses less digits than its factorization.

137521657 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1511247.

The product of its digits is 44100, while the sum is 37.

The square root of 137521657 is about 11726.9628207819. The cubic root of 137521657 is about 516.1671545971.

It can be divided in two parts, 1375 and 21657, that added together give a palindrome (23032).

The spelling of 137521657 in words is "one hundred thirty-seven million, five hundred twenty-one thousand, six hundred fifty-seven".