137509731 has 10 divisors (see below), whose sum is σ = 205415892. Its totient is φ = 91673100.

The previous prime is 137509727. The next prime is 137509741. The reversal of 137509731 is 137905731.

It is not a de Polignac number, because 137509731 - 2² = 137509727 is a prime.

It is a super-2 number, since 2×137509731² = 37817852239384722, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (137509711) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 848745 + ... + 848906.

Almost surely, 2^137509731 is an apocalyptic number.

137509731 is a deficient number, since it is larger than the sum of its proper divisors (67906161).

137509731 is an equidigital number, since it uses as much as digits as its factorization.

137509731 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1697663 (or 1697654 counting only the distinct ones).

The product of its (nonzero) digits is 19845, while the sum is 36.

The square root of 137509731 is about 11726.4543234517. The cubic root of 137509731 is about 516.1522333413.

The spelling of 137509731 in words is "one hundred thirty-seven million, five hundred nine thousand, seven hundred thirty-one".