99819431 has 2 divisors, whose sum is σ = 99819432. Its totient is φ = 99819430.

The previous prime is 99819373. The next prime is 99819439. The reversal of 99819431 is 13491899.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 99819431 - 2⁶ = 99819367 is a prime.

It is a super-2 number, since 2×99819431² = 19927837610327522, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (99819439) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 49909715 + 49909716.

It is an arithmetic number, because the mean of its divisors is an integer number (49909716).

Almost surely, 2^99819431 is an apocalyptic number.

99819431 is a deficient number, since it is larger than the sum of its proper divisors (1).

99819431 is an equidigital number, since it uses as much as digits as its factorization.

99819431 is an evil number, because the sum of its binary digits is even.

The product of its digits is 69984, while the sum is 44.

The square root of 99819431 is about 9990.9674706707. The cubic root of 99819431 is about 463.8793393524.

The spelling of 99819431 in words is "ninety-nine million, eight hundred nineteen thousand, four hundred thirty-one".