691963139806 has 32 divisors (see below), whose sum is σ = 1071016277760. Its totient is φ = 335098524096.

The previous prime is 691963139789. The next prime is 691963139807. The reversal of 691963139806 is 608931369196.

It is a super-4 number, since 4×691963139806⁴ (a number of 48 digits) contains 4444 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (691963139807) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10795705 + ... + 10859611.

It is an arithmetic number, because the mean of its divisors is an integer number (33469258680).

Almost surely, 2^691963139806 is an apocalyptic number.

691963139806 is a deficient number, since it is larger than the sum of its proper divisors (379053137954).

691963139806 is a wasteful number, since it uses less digits than its factorization.

691963139806 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 65008.

The product of its (nonzero) digits is 11337408, while the sum is 61.

The spelling of 691963139806 in words is "six hundred ninety-one billion, nine hundred sixty-three million, one hundred thirty-nine thousand, eight hundred six".