691339563 has 8 divisors (see below), whose sum is σ = 1024206800. Its totient is φ = 460893024.

The previous prime is 691339559. The next prime is 691339573. The reversal of 691339563 is 365933196.

It is not a de Polignac number, because 691339563 - 2² = 691339559 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (691339573) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12802558 + ... + 12802611.

It is an arithmetic number, because the mean of its divisors is an integer number (128025850).

Almost surely, 2^691339563 is an apocalyptic number.

691339563 is a deficient number, since it is larger than the sum of its proper divisors (332867237).

691339563 is a wasteful number, since it uses less digits than its factorization.

691339563 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25605178 (or 25605172 counting only the distinct ones).

The product of its digits is 393660, while the sum is 45.

The square root of 691339563 is about 26293.3368555610. The cubic root of 691339563 is about 884.2270642902.

The spelling of 691339563 in words is "six hundred ninety-one million, three hundred thirty-nine thousand, five hundred sixty-three".