31282981 has 2 divisors, whose sum is σ = 31282982. Its totient is φ = 31282980.

The previous prime is 31282969. The next prime is 31283017. The reversal of 31282981 is 18928213.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 29062881 + 2220100 = 5391^2 + 1490^2 .

It is a cyclic number.

It is not a de Polignac number, because 31282981 - 2⁹ = 31282469 is a prime.

It is a super-2 number, since 2×31282981² = 1957249800492722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31282961) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15641490 + 15641491.

It is an arithmetic number, because the mean of its divisors is an integer number (15641491).

Almost surely, 2^31282981 is an apocalyptic number.

It is an amenable number.

31282981 is a deficient number, since it is larger than the sum of its proper divisors (1).

31282981 is an equidigital number, since it uses as much as digits as its factorization.

31282981 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6912, while the sum is 34.

The square root of 31282981 is about 5593.1190761506. The cubic root of 31282981 is about 315.0910327306.

The spelling of 31282981 in words is "thirty-one million, two hundred eighty-two thousand, nine hundred eighty-one".