33131997 has 20 divisors (see below), whose sum is σ = 52407036. Its totient is φ = 20787840.

The previous prime is 33131993. The next prime is 33132013. The reversal of 33131997 is 79913133.

33131997 is a `hidden beast` number, since 331 + 319 + 9 + 7 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 30536676 + 2595321 = 5526^2 + 1611^2 .

It is not a de Polignac number, because 33131997 - 2² = 33131993 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (33131993) 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 in 19 ways as a sum of consecutive naturals, for example, 10654 + ... + 13407.

Almost surely, 2^33131997 is an apocalyptic number.

It is an amenable number.

33131997 is a deficient number, since it is larger than the sum of its proper divisors (19275039).

33131997 is a wasteful number, since it uses less digits than its factorization.

33131997 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24090 (or 24081 counting only the distinct ones).

The product of its digits is 15309, while the sum is 36.

The square root of 33131997 is about 5756.0400450310. The cubic root of 33131997 is about 321.1805255851.

The spelling of 33131997 in words is "thirty-three million, one hundred thirty-one thousand, nine hundred ninety-seven".