691201105920 has 896 divisors, whose sum is σ = 2673957242880. Its totient is φ = 168382955520.

The previous prime is 691201105913. The next prime is 691201105949. The reversal of 691201105920 is 29501102196.

691201105920 is a `hidden beast` number, since 69 + 1 + 2 + 0 + 1 + 1 + 0 + 592 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1883381577 + ... + 1883381943.

It is an arithmetic number, because the mean of its divisors is an integer number (2984327280).

Almost surely, 2^691201105920 is an apocalyptic number.

691201105920 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 691201105920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1336978621440).

691201105920 is an abundant number, since it is smaller than the sum of its proper divisors (1982756136960).

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

691201105920 is a wasteful number, since it uses less digits than its factorization.

691201105920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 551 (or 521 counting only the distinct ones).

The product of its (nonzero) digits is 9720, while the sum is 36.

It can be divided in two parts, 69120 and 1105920, that multiplied together give a square (76441190400 = 276480²).

The spelling of 691201105920 in words is "six hundred ninety-one billion, two hundred one million, one hundred five thousand, nine hundred twenty".