99707621 has 4 divisors (see below), whose sum is σ = 107377452. Its totient is φ = 92037792.

The previous prime is 99707617. The next prime is 99707623. The reversal of 99707621 is 12670799.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 12670799 = 229 ⋅55331.

It can be written as a sum of positive squares in 2 ways, for example, as 14145121 + 85562500 = 3761^2 + 9250^2 .

It is a cyclic number.

It is not a de Polignac number, because 99707621 - 2² = 99707617 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (99707623) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3834896 + ... + 3834921.

It is an arithmetic number, because the mean of its divisors is an integer number (26844363).

Almost surely, 2^99707621 is an apocalyptic number.

It is an amenable number.

99707621 is a deficient number, since it is larger than the sum of its proper divisors (7669831).

99707621 is a wasteful number, since it uses less digits than its factorization.

99707621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7669830.

The product of its (nonzero) digits is 47628, while the sum is 41.

The square root of 99707621 is about 9985.3703486651. The cubic root of 99707621 is about 463.7060740672.

The spelling of 99707621 in words is "ninety-nine million, seven hundred seven thousand, six hundred twenty-one".