31799813 has 2 divisors, whose sum is σ = 31799814. Its totient is φ = 31799812.

The previous prime is 31799767. The next prime is 31799821. The reversal of 31799813 is 31899713.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 31787044 + 12769 = 5638^2 + 113^2 .

It is a cyclic number.

It is not a de Polignac number, because 31799813 - 2⁸ = 31799557 is a prime.

It is a super-2 number, since 2×31799813² = 2022456213669938, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31799513) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15899906 + 15899907.

It is an arithmetic number, because the mean of its divisors is an integer number (15899907).

Almost surely, 2^31799813 is an apocalyptic number.

It is an amenable number.

31799813 is a deficient number, since it is larger than the sum of its proper divisors (1).

31799813 is an equidigital number, since it uses as much as digits as its factorization.

31799813 is an evil number, because the sum of its binary digits is even.

The product of its digits is 40824, while the sum is 41.

The square root of 31799813 is about 5639.1322914080. The cubic root of 31799813 is about 316.8167895153.

The spelling of 31799813 in words is "thirty-one million, seven hundred ninety-nine thousand, eight hundred thirteen".