691805711142 has 384 divisors, whose sum is σ = 1935290880000. Its totient is φ = 179338199040.

The previous prime is 691805711123. The next prime is 691805711263. The reversal of 691805711142 is 241117508196.

691805711142 is a `hidden beast` number, since 69 + 1 + 8 + 0 + 571 + 1 + 14 + 2 = 666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 1540769734 + ... + 1540770182.

It is an arithmetic number, because the mean of its divisors is an integer number (5039820000).

Almost surely, 2^691805711142 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 691805711142, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (967645440000).

691805711142 is an abundant number, since it is smaller than the sum of its proper divisors (1243485168858).

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

691805711142 is a wasteful number, since it uses less digits than its factorization.

691805711142 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 853 (or 834 counting only the distinct ones).

The product of its (nonzero) digits is 120960, while the sum is 45.

The spelling of 691805711142 in words is "six hundred ninety-one billion, eight hundred five million, seven hundred eleven thousand, one hundred forty-two".