99431 has 2 divisors, whose sum is σ = 99432. Its totient is φ = 99430.

The previous prime is 99409. The next prime is 99439. The reversal of 99431 is 13499.

It is a happy number.

It is a strong prime.

It is an emirp because it is prime and its reverse (13499) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 99431 - 2⁶ = 99367 is a prime.

It is a super-2 number, since 2×99431² = 19773047522, which contains 22 as substring.

It is a Chen prime.

It is a nialpdrome in base 10.

It is a self number, because there is not a number n which added to its sum of digits gives 99431.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (99439) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 49715 + 49716.

It is an arithmetic number, because the mean of its divisors is an integer number (49716).

2⁹⁹⁴³¹ is an apocalyptic number.

99431 is a deficient number, since it is larger than the sum of its proper divisors (1).

99431 is an equidigital number, since it uses as much as digits as its factorization.

99431 is an evil number, because the sum of its binary digits is even.

The product of its digits is 972, while the sum is 26.

The square root of 99431 is about 315.3268145908. The cubic root of 99431 is about 46.3276853641.

The spelling of 99431 in words is "ninety-nine thousand, four hundred thirty-one".