631791947 has 4 divisors (see below), whose sum is σ = 633701016. Its totient is φ = 629882880.

The previous prime is 631791917. The next prime is 631791949. The reversal of 631791947 is 749197136.

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 631791947 - 2¹⁴ = 631775563 is a prime.

It is a super-2 number, since 2×631791947² = 798322128588101618, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (631791949) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 954038 + ... + 954699.

It is an arithmetic number, because the mean of its divisors is an integer number (158425254).

Almost surely, 2^631791947 is an apocalyptic number.

631791947 is a deficient number, since it is larger than the sum of its proper divisors (1909069).

631791947 is a wasteful number, since it uses less digits than its factorization.

631791947 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1909068.

The product of its digits is 285768, while the sum is 47.

The square root of 631791947 is about 25135.4718873547. The cubic root of 631791947 is about 858.0739060590.

The spelling of 631791947 in words is "six hundred thirty-one million, seven hundred ninety-one thousand, nine hundred forty-seven".