31722013 has 8 divisors (see below), whose sum is σ = 32343416. Its totient is φ = 31104000.

The previous prime is 31721953. The next prime is 31722049. The reversal of 31722013 is 31022713.

It can be written as a sum of positive squares in 4 ways, for example, as 7387524 + 24334489 = 2718^2 + 4933^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 31722013 - 2¹³ = 31713821 is a prime.

It is a super-2 number, since 2×31722013² = 2012572217544338, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31722073) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 25813 + ... + 27013.

It is an arithmetic number, because the mean of its divisors is an integer number (4042927).

Almost surely, 2^31722013 is an apocalyptic number.

It is an amenable number.

31722013 is a deficient number, since it is larger than the sum of its proper divisors (621403).

31722013 is a wasteful number, since it uses less digits than its factorization.

31722013 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1695.

The product of its (nonzero) digits is 252, while the sum is 19.

The square root of 31722013 is about 5632.2298426112. The cubic root of 31722013 is about 316.5582085946.

Adding to 31722013 its reverse (31022713), we get a palindrome (62744726).

The spelling of 31722013 in words is "thirty-one million, seven hundred twenty-two thousand, thirteen".