31630140 has 36 divisors (see below), whose sum is σ = 95945304. Its totient is φ = 8434656.

The previous prime is 31630139. The next prime is 31630171. The reversal of 31630140 is 4103613.

31630140 is a `hidden beast` number, since 31 + 630 + 1 + 4 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 87682 + ... + 88041.

Almost surely, 2^31630140 is an apocalyptic number.

31630140 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

31630140 is an abundant number, since it is smaller than the sum of its proper divisors (64315164).

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

31630140 is a wasteful number, since it uses less digits than its factorization.

31630140 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 175738 (or 175733 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 18.

The square root of 31630140 is about 5624.0679227762. The cubic root of 31630140 is about 316.2523087731.

Adding to 31630140 its reverse (4103613), we get a palindrome (35733753).

The spelling of 31630140 in words is "thirty-one million, six hundred thirty thousand, one hundred forty".