631995979 has 2 divisors, whose sum is σ = 631995980. Its totient is φ = 631995978.

The previous prime is 631995943. The next prime is 631996003. The reversal of 631995979 is 979599136.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 631995979 - 2¹⁷ = 631864907 is a prime.

It is not a weakly prime, because it can be changed into another prime (631995919) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 315997989 + 315997990.

It is an arithmetic number, because the mean of its divisors is an integer number (315997990).

Almost surely, 2^631995979 is an apocalyptic number.

631995979 is a deficient number, since it is larger than the sum of its proper divisors (1).

631995979 is an equidigital number, since it uses as much as digits as its factorization.

631995979 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4133430, while the sum is 58.

The square root of 631995979 is about 25139.5302064299. The cubic root of 631995979 is about 858.1662654152.

The spelling of 631995979 in words is "six hundred thirty-one million, nine hundred ninety-five thousand, nine hundred seventy-nine".