31225013 has 4 divisors (see below), whose sum is σ = 31280460. Its totient is φ = 31169568.

The previous prime is 31224997. The next prime is 31225031. The reversal of 31225013 is 31052213.

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 20584369 + 10640644 = 4537^2 + 3262^2 .

It is a cyclic number.

It is not a de Polignac number, because 31225013 - 2⁴ = 31224997 is a prime.

It is a super-3 number, since 3×31225013³ (a number of 23 digits) contains 333 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 31224982 and 31225000.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31225213) 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, 26870 + ... + 28007.

It is an arithmetic number, because the mean of its divisors is an integer number (7820115).

Almost surely, 2^31225013 is an apocalyptic number.

It is an amenable number.

31225013 is a deficient number, since it is larger than the sum of its proper divisors (55447).

31225013 is an equidigital number, since it uses as much as digits as its factorization.

31225013 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55446.

The product of its (nonzero) digits is 180, while the sum is 17.

The square root of 31225013 is about 5587.9345916000. The cubic root of 31225013 is about 314.8962890291.

Adding to 31225013 its reverse (31052213), we get a palindrome (62277226).

The spelling of 31225013 in words is "thirty-one million, two hundred twenty-five thousand, thirteen".