31640130 has 48 divisors (see below), whose sum is σ = 86598720. Its totient is φ = 7992864.

The previous prime is 31640129. The next prime is 31640137. The reversal of 31640130 is 3104613.

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

It is not an unprimeable number, because it can be changed into a prime (31640137) by changing a digit.

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 23 ways as a sum of consecutive naturals, for example, 7542 + ... + 10961.

It is an arithmetic number, because the mean of its divisors is an integer number (1804140).

Almost surely, 2^31640130 is an apocalyptic number.

31640130 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

31640130 is an abundant number, since it is smaller than the sum of its proper divisors (54958590).

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

31640130 is a wasteful number, since it uses less digits than its factorization.

31640130 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18535 (or 18532 counting only the distinct ones).

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

The square root of 31640130 is about 5624.9559998279. The cubic root of 31640130 is about 316.2856001001.

Adding to 31640130 its reverse (3104613), we get a palindrome (34744743).

The spelling of 31640130 in words is "thirty-one million, six hundred forty thousand, one hundred thirty".