99920123231 has 2 divisors, whose sum is σ = 99920123232. Its totient is φ = 99920123230.

The previous prime is 99920123221. The next prime is 99920123263. The reversal of 99920123231 is 13232102999.

It is a weak prime.

It is an emirp because it is prime and its reverse (13232102999) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 99920123231 - 2¹⁰ = 99920122207 is a prime.

It is a super-2 number, since 2×99920123231² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (99920123201) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 49960061615 + 49960061616.

It is an arithmetic number, because the mean of its divisors is an integer number (49960061616).

Almost surely, 2^99920123231 is an apocalyptic number.

99920123231 is a deficient number, since it is larger than the sum of its proper divisors (1).

99920123231 is an equidigital number, since it uses as much as digits as its factorization.

99920123231 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 52488, while the sum is 41.

The spelling of 99920123231 in words is "ninety-nine billion, nine hundred twenty million, one hundred twenty-three thousand, two hundred thirty-one".