137978665 has 48 divisors (see below), whose sum is σ = 198169920. Its totient is φ = 91203840.

The previous prime is 137978657. The next prime is 137978671. The reversal of 137978665 is 566879731.

It is not a de Polignac number, because 137978665 - 2³ = 137978657 is a prime.

It is a super-2 number, since 2×137978665² = 38076223990364450, which contains 22 as substring.

It is a Smith number, since the sum of its digits (52) coincides with the sum of the digits of its prime factors.

It is a plaindrome in base 14.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 878767 + ... + 878923.

It is an arithmetic number, because the mean of its divisors is an integer number (4128540).

Almost surely, 2^137978665 is an apocalyptic number.

It is an amenable number.

137978665 is a deficient number, since it is larger than the sum of its proper divisors (60191255).

137978665 is a wasteful number, since it uses less digits than its factorization.

137978665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 250 (or 221 counting only the distinct ones).

The product of its digits is 1905120, while the sum is 52.

The square root of 137978665 is about 11746.4320114663. The cubic root of 137978665 is about 516.7382929951.

The spelling of 137978665 in words is "one hundred thirty-seven million, nine hundred seventy-eight thousand, six hundred sixty-five".