31323013405 has 4 divisors (see below), whose sum is σ = 37587616092. Its totient is φ = 25058410720.

The previous prime is 31323013399. The next prime is 31323013429. The reversal of 31323013405 is 50431032313.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 22491900729 + 8831112676 = 149973^2 + 93974^2 .

It is not a de Polignac number, because 31323013405 - 2⁹ = 31323012893 is a prime.

It is a super-2 number, since 2×31323013405² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 31323013405.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3132301336 + ... + 3132301345.

It is an arithmetic number, because the mean of its divisors is an integer number (9396904023).

Almost surely, 2^31323013405 is an apocalyptic number.

It is an amenable number.

31323013405 is a deficient number, since it is larger than the sum of its proper divisors (6264602687).

31323013405 is an equidigital number, since it uses as much as digits as its factorization.

31323013405 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6264602686.

The product of its (nonzero) digits is 3240, while the sum is 25.

Adding to 31323013405 its reverse (50431032313), we get a palindrome (81754045718).

The spelling of 31323013405 in words is "thirty-one billion, three hundred twenty-three million, thirteen thousand, four hundred five".