99749621 has 2 divisors, whose sum is σ = 99749622. Its totient is φ = 99749620.

The previous prime is 99749603. The next prime is 99749623. The reversal of 99749621 is 12694799.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 87422500 + 12327121 = 9350^2 + 3511^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-99749621 is a prime.

Together with 99749623, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (99749623) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 49874810 + 49874811.

It is an arithmetic number, because the mean of its divisors is an integer number (49874811).

Almost surely, 2^99749621 is an apocalyptic number.

It is an amenable number.

99749621 is a deficient number, since it is larger than the sum of its proper divisors (1).

99749621 is an equidigital number, since it uses as much as digits as its factorization.

99749621 is an evil number, because the sum of its binary digits is even.

The product of its digits is 244944, while the sum is 47.

The square root of 99749621 is about 9987.4732039691. The cubic root of 99749621 is about 463.7711741433.

The spelling of 99749621 in words is "ninety-nine million, seven hundred forty-nine thousand, six hundred twenty-one".