31386140 has 12 divisors (see below), whose sum is σ = 65910936. Its totient is φ = 12554448.

The previous prime is 31386133. The next prime is 31386143. The reversal of 31386140 is 4168313.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31386143) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 784634 + ... + 784673.

It is an arithmetic number, because the mean of its divisors is an integer number (5492578).

Almost surely, 2^31386140 is an apocalyptic number.

It is an amenable number.

31386140 is an abundant number, since it is smaller than the sum of its proper divisors (34524796).

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

31386140 is a wasteful number, since it uses less digits than its factorization.

31386140 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1569316 (or 1569314 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 26.

The square root of 31386140 is about 5602.3334424149. Note that the first 3 decimals coincide. The cubic root of 31386140 is about 315.4370015941.

The spelling of 31386140 in words is "thirty-one million, three hundred eighty-six thousand, one hundred forty".