31404431 has 2 divisors, whose sum is σ = 31404432. Its totient is φ = 31404430.

The previous prime is 31404427. The next prime is 31404437. The reversal of 31404431 is 13440413.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 31404431 - 2² = 31404427 is a prime.

It is a super-2 number, since 2×31404431² = 1972476572867522, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31404437) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15702215 + 15702216.

It is an arithmetic number, because the mean of its divisors is an integer number (15702216).

Almost surely, 2^31404431 is an apocalyptic number.

31404431 is a deficient number, since it is larger than the sum of its proper divisors (1).

31404431 is an equidigital number, since it uses as much as digits as its factorization.

31404431 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 576, while the sum is 20.

The square root of 31404431 is about 5603.9656494308. The cubic root of 31404431 is about 315.4982657674.

Adding to 31404431 its reverse (13440413), we get a palindrome (44844844).

The spelling of 31404431 in words is "thirty-one million, four hundred four thousand, four hundred thirty-one".