31289772 has 12 divisors (see below), whose sum is σ = 73009496. Its totient is φ = 10429920.

The previous prime is 31289749. The next prime is 31289777. The reversal of 31289772 is 27798213.

It is a tau number, because it is divible by the number of its divisors (12).

It is a self number, because there is not a number n which added to its sum of digits gives 31289772.

It is not an unprimeable number, because it can be changed into a prime (31289777) 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, 1303729 + ... + 1303752.

Almost surely, 2^31289772 is an apocalyptic number.

It is an amenable number.

31289772 is an abundant number, since it is smaller than the sum of its proper divisors (41719724).

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

31289772 is a wasteful number, since it uses less digits than its factorization.

31289772 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2607488 (or 2607486 counting only the distinct ones).

The product of its digits is 42336, while the sum is 39.

The square root of 31289772 is about 5593.7261284407. The cubic root of 31289772 is about 315.1138313718.

The spelling of 31289772 in words is "thirty-one million, two hundred eighty-nine thousand, seven hundred seventy-two".