31802013 has 6 divisors (see below), whose sum is σ = 45936254. Its totient is φ = 21201336.

The previous prime is 31801969. The next prime is 31802021. The reversal of 31802013 is 31020813.

It can be written as a sum of positive squares in only one way, i.e., 31775769 + 26244 = 5637^2 + 162^2 .

It is not a de Polignac number, because 31802013 - 2¹⁷ = 31670941 is a prime.

It is a super-2 number, since 2×31802013² = 2022736061704338, which contains 22 as substring.

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 (31802083) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1766770 + ... + 1766787.

Almost surely, 2^31802013 is an apocalyptic number.

It is an amenable number.

31802013 is a deficient number, since it is larger than the sum of its proper divisors (14134241).

31802013 is a wasteful number, since it uses less digits than its factorization.

31802013 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3533563 (or 3533560 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

The square root of 31802013 is about 5639.3273535059. The cubic root of 31802013 is about 316.8240954373.

Adding to 31802013 its reverse (31020813), we get a palindrome (62822826).

The spelling of 31802013 in words is "thirty-one million, eight hundred two thousand, thirteen".