137973978 has 24 divisors (see below), whose sum is σ = 304012800. Its totient is φ = 45211464.

The previous prime is 137973973. The next prime is 137974013. The reversal of 137973978 is 879379731.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (137973973) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 63898 + ... + 66021.

It is an arithmetic number, because the mean of its divisors is an integer number (12667200).

Almost surely, 2^137973978 is an apocalyptic number.

137973978 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

137973978 is an abundant number, since it is smaller than the sum of its proper divisors (166038822).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

137973978 is a wasteful number, since it uses less digits than its factorization.

137973978 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 129986 (or 129983 counting only the distinct ones).

The product of its digits is 2000376, while the sum is 54.

The square root of 137973978 is about 11746.2325023813. The cubic root of 137973978 is about 516.7324418977.

It can be divided in two parts, 1379 and 73978, that added together give a palindrome (75357).

The spelling of 137973978 in words is "one hundred thirty-seven million, nine hundred seventy-three thousand, nine hundred seventy-eight".