99611899940721 has 32 divisors (see below), whose sum is σ = 152058869803008. Its totient is φ = 56820184243200.

The previous prime is 99611899940689. The next prime is 99611899940723. The reversal of 99611899940721 is 12704999811699.

It is not a de Polignac number, because 99611899940721 - 2⁵ = 99611899940689 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (99611899940723) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 25006156 + ... + 28714658.

It is an arithmetic number, because the mean of its divisors is an integer number (4751839681344).

Almost surely, 2^{99611899940721} is an apocalyptic number.

It is an amenable number.

99611899940721 is a deficient number, since it is larger than the sum of its proper divisors (52446969862287).

99611899940721 is a wasteful number, since it uses less digits than its factorization.

99611899940721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3710781.

The product of its (nonzero) digits is 158723712, while the sum is 75.

The spelling of 99611899940721 in words is "ninety-nine trillion, six hundred eleven billion, eight hundred ninety-nine million, nine hundred forty thousand, seven hundred twenty-one".