31321901 has 4 divisors (see below), whose sum is σ = 33731292. Its totient is φ = 28912512.

The previous prime is 31321889. The next prime is 31321907. The reversal of 31321901 is 10912313.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 10912313 = 149 ⋅73237.

It can be written as a sum of positive squares in 2 ways, for example, as 1357225 + 29964676 = 1165^2 + 5474^2 .

It is a cyclic number.

It is not a de Polignac number, because 31321901 - 2¹⁸ = 31059757 is a prime.

It is a super-2 number, since 2×31321901² = 1962122964507602, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31321907) 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, 1204676 + ... + 1204701.

It is an arithmetic number, because the mean of its divisors is an integer number (8432823).

Almost surely, 2^31321901 is an apocalyptic number.

It is an amenable number.

31321901 is a deficient number, since it is larger than the sum of its proper divisors (2409391).

31321901 is a wasteful number, since it uses less digits than its factorization.

31321901 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2409390.

The product of its (nonzero) digits is 162, while the sum is 20.

The square root of 31321901 is about 5596.5972697703. The cubic root of 31321901 is about 315.2216496602.

The spelling of 31321901 in words is "thirty-one million, three hundred twenty-one thousand, nine hundred one".