31311013 has 4 divisors (see below), whose sum is σ = 31598380. Its totient is φ = 31023648.

The previous prime is 31311011. The next prime is 31311029. The reversal of 31311013 is 31011313.

It is a happy number.

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 9474084 + 21836929 = 3078^2 + 4673^2 .

It is a cyclic number.

It is not a de Polignac number, because 31311013 - 2¹ = 31311011 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 31310984 and 31311002.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31311011) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 143520 + ... + 143737.

It is an arithmetic number, because the mean of its divisors is an integer number (7899595).

Almost surely, 2^31311013 is an apocalyptic number.

It is an amenable number.

31311013 is a deficient number, since it is larger than the sum of its proper divisors (287367).

31311013 is a wasteful number, since it uses less digits than its factorization.

31311013 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 287366.

The product of its (nonzero) digits is 27, while the sum is 13.

The square root of 31311013 is about 5595.6244513012. The cubic root of 31311013 is about 315.1851200438.

Adding to 31311013 its reverse (31011313), we get a palindrome (62322326).

The spelling of 31311013 in words is "thirty-one million, three hundred eleven thousand, thirteen".