691880255487 has 24 divisors (see below), whose sum is σ = 1014252954000. Its totient is φ = 454404981888.

The previous prime is 691880255477. The next prime is 691880255513. The reversal of 691880255487 is 784552088196.

691880255487 is a `hidden beast` number, since 6 + 9 + 1 + 8 + 80 + 2 + 5 + 548 + 7 = 666.

It is not a de Polignac number, because 691880255487 - 2²² = 691876061183 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (691880255477) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 48612 + ... + 1177337.

It is an arithmetic number, because the mean of its divisors is an integer number (42260539750).

Almost surely, 2^691880255487 is an apocalyptic number.

691880255487 is a deficient number, since it is larger than the sum of its proper divisors (322372698513).

691880255487 is a wasteful number, since it uses less digits than its factorization.

691880255487 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1226887 (or 1226884 counting only the distinct ones).

The product of its (nonzero) digits is 38707200, while the sum is 63.

The spelling of 691880255487 in words is "six hundred ninety-one billion, eight hundred eighty million, two hundred fifty-five thousand, four hundred eighty-seven".