31121072 has 20 divisors (see below), whose sum is σ = 60419496. Its totient is φ = 15528960.

The previous prime is 31121063. The next prime is 31121081. The reversal of 31121072 is 27012113.

It is an interprime number because it is at equal distance from previous prime (31121063) and next prime (31121081).

It is a super-2 number, since 2×31121072² = 1937042244858368, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 31121072.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7547 + ... + 10917.

Almost surely, 2^31121072 is an apocalyptic number.

It is an amenable number.

31121072 is a deficient number, since it is larger than the sum of its proper divisors (29298424).

31121072 is a wasteful number, since it uses less digits than its factorization.

31121072 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3956 (or 3950 counting only the distinct ones).

The product of its (nonzero) digits is 84, while the sum is 17.

The square root of 31121072 is about 5578.6263542202. The cubic root of 31121072 is about 314.5464944577.

Adding to 31121072 its reverse (27012113), we get a palindrome (58133185).

The spelling of 31121072 in words is "thirty-one million, one hundred twenty-one thousand, seventy-two".