31574981 has 2 divisors, whose sum is σ = 31574982. Its totient is φ = 31574980.

The previous prime is 31574969. The next prime is 31574989. The reversal of 31574981 is 18947513.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 28718881 + 2856100 = 5359^2 + 1690^2 .

It is a cyclic number.

It is not a de Polignac number, because 31574981 - 2¹⁰ = 31573957 is a prime.

It is a super-2 number, since 2×31574981² = 1993958850300722, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31574989) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15787490 + 15787491.

It is an arithmetic number, because the mean of its divisors is an integer number (15787491).

Almost surely, 2^31574981 is an apocalyptic number.

It is an amenable number.

31574981 is a deficient number, since it is larger than the sum of its proper divisors (1).

31574981 is an equidigital number, since it uses as much as digits as its factorization.

31574981 is an evil number, because the sum of its binary digits is even.

The product of its digits is 30240, while the sum is 38.

The square root of 31574981 is about 5619.1619481912. The cubic root of 31574981 is about 316.0683670108.

The spelling of 31574981 in words is "thirty-one million, five hundred seventy-four thousand, nine hundred eighty-one".