31242013 has 4 divisors (see below), whose sum is σ = 34082208. Its totient is φ = 28401820.

The previous prime is 31242007. The next prime is 31242049. The reversal of 31242013 is 31024213.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 31024213 = 11 ⋅2820383.

It is a cyclic number.

It is not a de Polignac number, because 31242013 - 2¹³ = 31233821 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31243013) 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, 1420081 + ... + 1420102.

It is an arithmetic number, because the mean of its divisors is an integer number (8520552).

Almost surely, 2^31242013 is an apocalyptic number.

It is an amenable number.

31242013 is a deficient number, since it is larger than the sum of its proper divisors (2840195).

31242013 is a wasteful number, since it uses less digits than its factorization.

31242013 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2840194.

The product of its (nonzero) digits is 144, while the sum is 16.

The square root of 31242013 is about 5589.4555191002. The cubic root of 31242013 is about 314.9534255488.

Adding to 31242013 its reverse (31024213), we get a palindrome (62266226).

The spelling of 31242013 in words is "thirty-one million, two hundred forty-two thousand, thirteen".