631211899 has 2 divisors, whose sum is σ = 631211900. Its totient is φ = 631211898.

The previous prime is 631211879. The next prime is 631212013. The reversal of 631211899 is 998112136.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 631211899 - 2⁷ = 631211771 is a prime.

It is a super-2 number, since 2×631211899² = 796856922878372402, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (631211849) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 315605949 + 315605950.

It is an arithmetic number, because the mean of its divisors is an integer number (315605950).

Almost surely, 2^631211899 is an apocalyptic number.

631211899 is a deficient number, since it is larger than the sum of its proper divisors (1).

631211899 is an equidigital number, since it uses as much as digits as its factorization.

631211899 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 23328, while the sum is 40.

The square root of 631211899 is about 25123.9308031208. The cubic root of 631211899 is about 857.8112265207.

The spelling of 631211899 in words is "six hundred thirty-one million, two hundred eleven thousand, eight hundred ninety-nine".