31242788 has 6 divisors (see below), whose sum is σ = 54674886. Its totient is φ = 15621392.

The previous prime is 31242751. The next prime is 31242791. The reversal of 31242788 is 88724213.

It can be written as a sum of positive squares in only one way, i.e., 28815424 + 2427364 = 5368^2 + 1558^2 .

It is a super-2 number, since 2×31242788² = 1952223604025888, which contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3905345 + ... + 3905352.

It is an arithmetic number, because the mean of its divisors is an integer number (9112481).

Almost surely, 2^31242788 is an apocalyptic number.

It is an amenable number.

31242788 is a deficient number, since it is larger than the sum of its proper divisors (23432098).

31242788 is a wasteful number, since it uses less digits than its factorization.

31242788 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7810701 (or 7810699 counting only the distinct ones).

The product of its digits is 21504, while the sum is 35.

The square root of 31242788 is about 5589.5248456376. The cubic root of 31242788 is about 314.9560298078.

The spelling of 31242788 in words is "thirty-one million, two hundred forty-two thousand, seven hundred eighty-eight".