31871369 has 2 divisors, whose sum is σ = 31871370. Its totient is φ = 31871368.

The previous prime is 31871363. The next prime is 31871407. The reversal of 31871369 is 96317813.

It is an a-pointer prime, because the next prime (31871407) can be obtained adding 31871369 to its sum of digits (38).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 29560969 + 2310400 = 5437^2 + 1520^2 .

It is a cyclic number.

It is not a de Polignac number, because 31871369 - 2²⁰ = 30822793 is a prime.

It is a super-2 number, since 2×31871369² = 2031568323868322, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (31871363) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15935684 + 15935685.

It is an arithmetic number, because the mean of its divisors is an integer number (15935685).

Almost surely, 2^31871369 is an apocalyptic number.

It is an amenable number.

31871369 is a deficient number, since it is larger than the sum of its proper divisors (1).

31871369 is an equidigital number, since it uses as much as digits as its factorization.

31871369 is an evil number, because the sum of its binary digits is even.

The product of its digits is 27216, while the sum is 38.

The square root of 31871369 is about 5645.4733193949. The cubic root of 31871369 is about 317.0542454115.

The spelling of 31871369 in words is "thirty-one million, eight hundred seventy-one thousand, three hundred sixty-nine".