99721715976 has 96 divisors (see below), whose sum is σ = 280195100640. Its totient is φ = 33227221248.

The previous prime is 99721715971. The next prime is 99721715993. The reversal of 99721715976 is 67951712799.

It is not an unprimeable number, because it can be changed into a prime (99721715971) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 5622915 + ... + 5640621.

It is an arithmetic number, because the mean of its divisors is an integer number (2918698965).

Almost surely, 2^99721715976 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 99721715976, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (140097550320).

99721715976 is an abundant number, since it is smaller than the sum of its proper divisors (180473384664).

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

99721715976 is a wasteful number, since it uses less digits than its factorization.

99721715976 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20625 (or 20609 counting only the distinct ones).

The product of its digits is 15002820, while the sum is 63.

The spelling of 99721715976 in words is "ninety-nine billion, seven hundred twenty-one million, seven hundred fifteen thousand, nine hundred seventy-six".