31819138 has 32 divisors (see below), whose sum is σ = 54852336. Its totient is φ = 13713408.

The previous prime is 31819127. The next prime is 31819163. The reversal of 31819138 is 83191813.

It is a happy number.

It can be written as a sum of positive squares in 8 ways, for example, as 10870209 + 20948929 = 3297^2 + 4577^2 .

It is a Harshad number since it is a multiple of its sum of digits (34).

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 85120 + ... + 85492.

Almost surely, 2^31819138 is an apocalyptic number.

31819138 is a deficient number, since it is larger than the sum of its proper divisors (23033198).

31819138 is a wasteful number, since it uses less digits than its factorization.

31819138 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 598.

The product of its digits is 5184, while the sum is 34.

The square root of 31819138 is about 5640.8455040003. The cubic root of 31819138 is about 316.8809538826.

The spelling of 31819138 in words is "thirty-one million, eight hundred nineteen thousand, one hundred thirty-eight".