31240402013 has 4 divisors (see below), whose sum is σ = 31242938460. Its totient is φ = 31237865568.

The previous prime is 31240401967. The next prime is 31240402099. The reversal of 31240402013 is 31020404213.

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 8385614329 + 22854787684 = 91573^2 + 151178^2 .

It is a cyclic number.

It is not a de Polignac number, because 31240402013 - 2¹⁴ = 31240385629 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31240401013) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1249658 + ... + 1274411.

It is an arithmetic number, because the mean of its divisors is an integer number (7810734615).

Almost surely, 2^31240402013 is an apocalyptic number.

It is an amenable number.

31240402013 is a deficient number, since it is larger than the sum of its proper divisors (2536447).

31240402013 is a wasteful number, since it uses less digits than its factorization.

31240402013 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2536446.

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

Adding to 31240402013 its reverse (31020404213), we get a palindrome (62260806226).

The spelling of 31240402013 in words is "thirty-one billion, two hundred forty million, four hundred two thousand, thirteen".