31643893 has 2 divisors, whose sum is σ = 31643894. Its totient is φ = 31643892.

The previous prime is 31643879. The next prime is 31643903. The reversal of 31643893 is 39834613.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 29354724 + 2289169 = 5418^2 + 1513^2 .

It is a cyclic number.

It is not a de Polignac number, because 31643893 - 2¹³ = 31635701 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31643813) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15821946 + 15821947.

It is an arithmetic number, because the mean of its divisors is an integer number (15821947).

Almost surely, 2^31643893 is an apocalyptic number.

It is an amenable number.

31643893 is a deficient number, since it is larger than the sum of its proper divisors (1).

31643893 is an equidigital number, since it uses as much as digits as its factorization.

31643893 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 46656, while the sum is 37.

The square root of 31643893 is about 5625.2904813885. The cubic root of 31643893 is about 316.2981383496.

The spelling of 31643893 in words is "thirty-one million, six hundred forty-three thousand, eight hundred ninety-three".