137256731 has 4 divisors (see below), whose sum is σ = 140448792. Its totient is φ = 134064672.

The previous prime is 137256683. The next prime is 137256781. The reversal of 137256731 is 137652731.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 137256731 - 2¹⁰ = 137255707 is a prime.

It is a super-2 number, since 2×137256731² = 37678820409612722, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 137256691 and 137256700.

It is not an unprimeable number, because it can be changed into a prime (137256781) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1595966 + ... + 1596051.

It is an arithmetic number, because the mean of its divisors is an integer number (35112198).

Almost surely, 2^137256731 is an apocalyptic number.

137256731 is a deficient number, since it is larger than the sum of its proper divisors (3192061).

137256731 is an equidigital number, since it uses as much as digits as its factorization.

137256731 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3192060.

The product of its digits is 26460, while the sum is 35.

The square root of 137256731 is about 11715.6617824176. The cubic root of 137256731 is about 515.8354880379.

The spelling of 137256731 in words is "one hundred thirty-seven million, two hundred fifty-six thousand, seven hundred thirty-one".