7721640576 has 320 divisors, whose sum is σ = 25192490400. Its totient is φ = 2333214720.

The previous prime is 7721640547. The next prime is 7721640581. The reversal of 7721640576 is 6750461277.

7721640576 is a `hidden beast` number, since 7 + 72 + 1 + 6 + 4 + 0 + 576 = 666.

It is a super-2 number, since 2×7721640576² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 7951771 + ... + 7952741.

Almost surely, 2^7721640576 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 7721640576, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (12596245200).

7721640576 is an abundant number, since it is smaller than the sum of its proper divisors (17470849824).

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

7721640576 is a wasteful number, since it uses less digits than its factorization.

7721640576 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1069 (or 1048 counting only the distinct ones).

The product of its (nonzero) digits is 493920, while the sum is 45.

The square root of 7721640576 is about 87872.8659826229. The cubic root of 7721640576 is about 1976.5290152596.

The spelling of 7721640576 in words is "seven billion, seven hundred twenty-one million, six hundred forty thousand, five hundred seventy-six".