691463961 has 12 divisors (see below), whose sum is σ = 999052288. Its totient is φ = 460850904.

The previous prime is 691463947. The next prime is 691463977. The reversal of 691463961 is 169364196.

691463961 is a `hidden beast` number, since 6 + 9 + 1 + 4 + 639 + 6 + 1 = 666.

It is not a de Polignac number, because 691463961 - 2⁷ = 691463833 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (691463911) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 35016 + ... + 51078.

Almost surely, 2^691463961 is an apocalyptic number.

It is an amenable number.

691463961 is a deficient number, since it is larger than the sum of its proper divisors (307588327).

691463961 is a wasteful number, since it uses less digits than its factorization.

691463961 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20852 (or 20849 counting only the distinct ones).

The product of its digits is 209952, while the sum is 45.

The square root of 691463961 is about 26295.7023294682. The cubic root of 691463961 is about 884.2800963493.

The spelling of 691463961 in words is "six hundred ninety-one million, four hundred sixty-three thousand, nine hundred sixty-one".