691880255492 has 6 divisors (see below), whose sum is σ = 1210790447118. Its totient is φ = 345940127744.

The previous prime is 691880255477. The next prime is 691880255513. The reversal of 691880255492 is 294552088196.

It can be written as a sum of positive squares in only one way, i.e., 640230420736 + 51649834756 = 800144^2 + 227266^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 86485031933 + ... + 86485031940.

It is an arithmetic number, because the mean of its divisors is an integer number (201798407853).

Almost surely, 2^691880255492 is an apocalyptic number.

It is an amenable number.

691880255492 is a deficient number, since it is larger than the sum of its proper divisors (518910191626).

691880255492 is a wasteful number, since it uses less digits than its factorization.

691880255492 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 172970063877 (or 172970063875 counting only the distinct ones).

The product of its (nonzero) digits is 12441600, while the sum is 59.

The spelling of 691880255492 in words is "six hundred ninety-one billion, eight hundred eighty million, two hundred fifty-five thousand, four hundred ninety-two".