31693789 has 2 divisors, whose sum is σ = 31693790. Its totient is φ = 31693788.

The previous prime is 31693787. The next prime is 31693801. The reversal of 31693789 is 98739613.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 27144100 + 4549689 = 5210^2 + 2133^2 .

It is a cyclic number.

It is not a de Polignac number, because 31693789 - 2¹ = 31693787 is a prime.

It is a super-2 number, since 2×31693789² = 2008992522353042, which contains 22 as substring.

Together with 31693787, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31693787) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15846894 + 15846895.

It is an arithmetic number, because the mean of its divisors is an integer number (15846895).

Almost surely, 2^31693789 is an apocalyptic number.

It is an amenable number.

31693789 is a deficient number, since it is larger than the sum of its proper divisors (1).

31693789 is an equidigital number, since it uses as much as digits as its factorization.

31693789 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 244944, while the sum is 46.

The square root of 31693789 is about 5629.7237054761. The cubic root of 31693789 is about 316.4642970474.

The spelling of 31693789 in words is "thirty-one million, six hundred ninety-three thousand, seven hundred eighty-nine".