31690138 has 16 divisors (see below), whose sum is σ = 50184000. Its totient is φ = 14967072.

The previous prime is 31690133. The next prime is 31690151. The reversal of 31690138 is 83109613.

It is not an unprimeable number, because it can be changed into a prime (31690133) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 14523 + ... + 16561.

It is an arithmetic number, because the mean of its divisors is an integer number (3136500).

Almost surely, 2^31690138 is an apocalyptic number.

31690138 is a gapful number since it is divisible by the number (38) formed by its first and last digit.

31690138 is a deficient number, since it is larger than the sum of its proper divisors (18493862).

31690138 is a wasteful number, since it uses less digits than its factorization.

31690138 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2469.

The product of its (nonzero) digits is 3888, while the sum is 31.

The square root of 31690138 is about 5629.3994351085. The cubic root of 31690138 is about 316.4521447661.

The spelling of 31690138 in words is "thirty-one million, six hundred ninety thousand, one hundred thirty-eight".