31683989 has 4 divisors (see below), whose sum is σ = 31734060. Its totient is φ = 31633920.

The previous prime is 31683973. The next prime is 31683997. The reversal of 31683989 is 98938613.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 24581764 + 7102225 = 4958^2 + 2665^2 .

It is a cyclic number.

It is not a de Polignac number, because 31683989 - 2⁴ = 31683973 is a prime.

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 (31683929) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 24074 + ... + 25355.

It is an arithmetic number, because the mean of its divisors is an integer number (7933515).

Almost surely, 2^31683989 is an apocalyptic number.

It is an amenable number.

31683989 is a deficient number, since it is larger than the sum of its proper divisors (50071).

31683989 is an equidigital number, since it uses as much as digits as its factorization.

31683989 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 50070.

The product of its digits is 279936, while the sum is 47.

The square root of 31683989 is about 5628.8532579914. The cubic root of 31683989 is about 316.4316758313.

The spelling of 31683989 in words is "thirty-one million, six hundred eighty-three thousand, nine hundred eighty-nine".