31667969 has 2 divisors, whose sum is σ = 31667970. Its totient is φ = 31667968.

The previous prime is 31667963. The next prime is 31667981. The reversal of 31667969 is 96976613.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 31225744 + 442225 = 5588^2 + 665^2 .

It is an emirp because it is prime and its reverse (96976613) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 31667969 - 2²⁴ = 14890753 is a prime.

It is a super-2 number, since 2×31667969² = 2005720521169922, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (31667963) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15833984 + 15833985.

It is an arithmetic number, because the mean of its divisors is an integer number (15833985).

Almost surely, 2^31667969 is an apocalyptic number.

It is an amenable number.

31667969 is a deficient number, since it is larger than the sum of its proper divisors (1).

31667969 is an equidigital number, since it uses as much as digits as its factorization.

31667969 is an evil number, because the sum of its binary digits is even.

The product of its digits is 367416, while the sum is 47.

The square root of 31667969 is about 5627.4300528749. The cubic root of 31667969 is about 316.3783356405.

The spelling of 31667969 in words is "thirty-one million, six hundred sixty-seven thousand, nine hundred sixty-nine".