691474159656 has 576 divisors, whose sum is σ = 2459100384000. Its totient is φ = 173903708160.

The previous prime is 691474159613. The next prime is 691474159669. The reversal of 691474159656 is 656951474196.

691474159656 is a `hidden beast` number, since 6 + 9 + 1 + 474 + 159 + 6 + 5 + 6 = 666.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a junction number, because it is equal to n+sod(n) for n = 691474159593 and 691474159602.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 90020136 + ... + 90027816.

It is an arithmetic number, because the mean of its divisors is an integer number (4269271500).

Almost surely, 2^691474159656 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 691474159656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1229550192000).

691474159656 is an abundant number, since it is smaller than the sum of its proper divisors (1767626224344).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

691474159656 is a wasteful number, since it uses less digits than its factorization.

691474159656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7822 (or 7808 counting only the distinct ones).

The product of its digits is 48988800, while the sum is 63.

The spelling of 691474159656 in words is "six hundred ninety-one billion, four hundred seventy-four million, one hundred fifty-nine thousand, six hundred fifty-six".