630643691 has 4 divisors (see below), whose sum is σ = 630727272. Its totient is φ = 630560112.

The previous prime is 630643669. The next prime is 630643729. The reversal of 630643691 is 196346036.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 630643691 - 2⁶ = 630643627 is a prime.

It is a super-2 number, since 2×630643691² = 795422929996206962, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (630693691) 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 in 3 ways as a sum of consecutive naturals, for example, 29210 + ... + 45983.

It is an arithmetic number, because the mean of its divisors is an integer number (157681818).

Almost surely, 2^630643691 is an apocalyptic number.

630643691 is a deficient number, since it is larger than the sum of its proper divisors (83581).

630643691 is an equidigital number, since it uses as much as digits as its factorization.

630643691 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 83580.

The product of its (nonzero) digits is 69984, while the sum is 38.

The square root of 630643691 is about 25112.6201540182. The cubic root of 630643691 is about 857.5537527468.

The spelling of 630643691 in words is "six hundred thirty million, six hundred forty-three thousand, six hundred ninety-one".