31405423 has 32 divisors (see below), whose sum is σ = 39680000. Its totient is φ = 24766560.

The previous prime is 31405411. The next prime is 31405441. The reversal of 31405423 is 32450413.

It is not a de Polignac number, because 31405423 - 2¹⁷ = 31274351 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 31405394 and 31405403.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31405453) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 397498 + ... + 397576.

It is an arithmetic number, because the mean of its divisors is an integer number (1240000).

Almost surely, 2^31405423 is an apocalyptic number.

31405423 is a deficient number, since it is larger than the sum of its proper divisors (8274577).

31405423 is an equidigital number, since it uses as much as digits as its factorization.

31405423 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 180 (or 166 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 22.

The square root of 31405423 is about 5604.0541574828. The cubic root of 31405423 is about 315.5015877082.

Adding to 31405423 its reverse (32450413), we get a palindrome (63855836).

The spelling of 31405423 in words is "thirty-one million, four hundred five thousand, four hundred twenty-three".