671961961 has 32 divisors (see below), whose sum is σ = 800593920. Its totient is φ = 557409600.

The previous prime is 671961947. The next prime is 671961973. The reversal of 671961961 is 169169176.

It is not a de Polignac number, because 671961961 - 2²³ = 663573353 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (671961911) 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 31 ways as a sum of consecutive naturals, for example, 657631 + ... + 658651.

It is an arithmetic number, because the mean of its divisors is an integer number (25018560).

Almost surely, 2^671961961 is an apocalyptic number.

It is an amenable number.

671961961 is a deficient number, since it is larger than the sum of its proper divisors (128631959).

671961961 is a wasteful number, since it uses less digits than its factorization.

671961961 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1165.

The product of its digits is 122472, while the sum is 46.

The square root of 671961961 is about 25922.2290901072. The cubic root of 671961961 is about 875.8873006292.

The spelling of 671961961 in words is "six hundred seventy-one million, nine hundred sixty-one thousand, nine hundred sixty-one".