669771631 has 2 divisors, whose sum is σ = 669771632. Its totient is φ = 669771630.

The previous prime is 669771629. The next prime is 669771637. The reversal of 669771631 is 136177966.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 669771631 - 2¹ = 669771629 is a prime.

It is a super-2 number, since 2×669771631² = 897188075384800322, which contains 22 as substring.

Together with 669771629, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (669771637) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 334885815 + 334885816.

It is an arithmetic number, because the mean of its divisors is an integer number (334885816).

Almost surely, 2^669771631 is an apocalyptic number.

669771631 is a deficient number, since it is larger than the sum of its proper divisors (1).

669771631 is an equidigital number, since it uses as much as digits as its factorization.

669771631 is an evil number, because the sum of its binary digits is even.

The product of its digits is 285768, while the sum is 46.

The square root of 669771631 is about 25879.9465030359. The cubic root of 669771631 is about 874.9345827556.

The spelling of 669771631 in words is "six hundred sixty-nine million, seven hundred seventy-one thousand, six hundred thirty-one".