691963660390 has 16 divisors (see below), whose sum is σ = 1245763267200. Its totient is φ = 276734646720.

The previous prime is 691963660357. The next prime is 691963660391. The reversal of 691963660390 is 93066369196.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (691963660391) 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, 6294966 + ... + 6403945.

It is an arithmetic number, because the mean of its divisors is an integer number (77860204200).

Almost surely, 2^691963660390 is an apocalyptic number.

691963660390 is a deficient number, since it is larger than the sum of its proper divisors (553799606810).

691963660390 is a wasteful number, since it uses less digits than its factorization.

691963660390 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12704367.

The product of its (nonzero) digits is 8503056, while the sum is 58.

The spelling of 691963660390 in words is "six hundred ninety-one billion, nine hundred sixty-three million, six hundred sixty thousand, three hundred ninety".