31189940 has 24 divisors (see below), whose sum is σ = 65641632. Its totient is φ = 12448800.

The previous prime is 31189913. The next prime is 31189957. The reversal of 31189940 is 4998113.

It is a self number, because there is not a number n which added to its sum of digits gives 31189940.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9515 + ... + 12365.

It is an arithmetic number, because the mean of its divisors is an integer number (2735068).

Almost surely, 2^31189940 is an apocalyptic number.

It is an amenable number.

31189940 is an abundant number, since it is smaller than the sum of its proper divisors (34451692).

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

31189940 is a wasteful number, since it uses less digits than its factorization.

31189940 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3407 (or 3405 counting only the distinct ones).

The product of its (nonzero) digits is 7776, while the sum is 35.

The square root of 31189940 is about 5584.7954304522. The cubic root of 31189940 is about 314.7783441061.

The spelling of 31189940 in words is "thirty-one million, one hundred eighty-nine thousand, nine hundred forty".