137531987 has 4 divisors (see below), whose sum is σ = 137658456. Its totient is φ = 137405520.

The previous prime is 137531981. The next prime is 137532001. The reversal of 137531987 is 789135731.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 789135731 = 3643 ⋅216617.

It is a cyclic number.

It is not a de Polignac number, because 137531987 - 2¹⁴ = 137515603 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (137531981) 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 3 ways as a sum of consecutive naturals, for example, 61589 + ... + 63782.

It is an arithmetic number, because the mean of its divisors is an integer number (34414614).

Almost surely, 2^137531987 is an apocalyptic number.

137531987 is a deficient number, since it is larger than the sum of its proper divisors (126469).

137531987 is a wasteful number, since it uses less digits than its factorization.

137531987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 126468.

The product of its digits is 158760, while the sum is 44.

The square root of 137531987 is about 11727.4032505069. The cubic root of 137531987 is about 516.1800783147.

The spelling of 137531987 in words is "one hundred thirty-seven million, five hundred thirty-one thousand, nine hundred eighty-seven".