31189420 has 24 divisors (see below), whose sum is σ = 65981664. Its totient is φ = 12383616.

The previous prime is 31189381. The next prime is 31189429. The reversal of 31189420 is 2498113.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (31189429) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2952 + ... + 8431.

It is an arithmetic number, because the mean of its divisors is an integer number (2749236).

Almost surely, 2^31189420 is an apocalyptic number.

It is an amenable number.

31189420 is an abundant number, since it is smaller than the sum of its proper divisors (34792244).

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

31189420 is a wasteful number, since it uses less digits than its factorization.

31189420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11529 (or 11527 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 28.

The square root of 31189420 is about 5584.7488752853. The cubic root of 31189420 is about 314.7765947637.

The spelling of 31189420 in words is "thirty-one million, one hundred eighty-nine thousand, four hundred twenty".