691977589814 has 16 divisors (see below), whose sum is σ = 1218308035488. Its totient is φ = 288546639552.

The previous prime is 691977589769. The next prime is 691977589837. The reversal of 691977589814 is 418985779196.

It is a Harshad number since it is a multiple of its sum of digits (74).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 667931519 + ... + 667932554.

It is an arithmetic number, because the mean of its divisors is an integer number (76144252218).

Almost surely, 2^691977589814 is an apocalyptic number.

691977589814 is a deficient number, since it is larger than the sum of its proper divisors (526330445674).

691977589814 is a wasteful number, since it uses less digits than its factorization.

691977589814 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1335864119.

The product of its digits is 274337280, while the sum is 74.

The spelling of 691977589814 in words is "six hundred ninety-one billion, nine hundred seventy-seven million, five hundred eighty-nine thousand, eight hundred fourteen".