631404139 has 2 divisors, whose sum is σ = 631404140. Its totient is φ = 631404138.

The previous prime is 631404133. The next prime is 631404197. The reversal of 631404139 is 931404136.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 631404139 - 2¹⁵ = 631371371 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 631404139.

It is not a weakly prime, because it can be changed into another prime (631404133) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 315702069 + 315702070.

It is an arithmetic number, because the mean of its divisors is an integer number (315702070).

Almost surely, 2^631404139 is an apocalyptic number.

631404139 is a deficient number, since it is larger than the sum of its proper divisors (1).

631404139 is an equidigital number, since it uses as much as digits as its factorization.

631404139 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 7776, while the sum is 31.

The square root of 631404139 is about 25127.7563463195. The cubic root of 631404139 is about 857.8983018183.

The spelling of 631404139 in words is "six hundred thirty-one million, four hundred four thousand, one hundred thirty-nine".