691772589540 has 288 divisors, whose sum is σ = 2292466176000. Its totient is φ = 174623236992.

The previous prime is 691772589511. The next prime is 691772589551. The reversal of 691772589540 is 45985277196.

691772589540 is a `hidden beast` number, since 6 + 9 + 1 + 7 + 7 + 2 + 5 + 89 + 540 = 666.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 162423931 + ... + 162428189.

It is an arithmetic number, because the mean of its divisors is an integer number (7959952000).

Almost surely, 2^691772589540 is an apocalyptic number.

691772589540 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 691772589540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1146233088000).

691772589540 is an abundant number, since it is smaller than the sum of its proper divisors (1600693586460).

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

691772589540 is a wasteful number, since it uses less digits than its factorization.

691772589540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6061 (or 6047 counting only the distinct ones).

The product of its (nonzero) digits is 38102400, while the sum is 63.

The spelling of 691772589540 in words is "six hundred ninety-one billion, seven hundred seventy-two million, five hundred eighty-nine thousand, five hundred forty".