33997391 has 4 divisors (see below), whose sum is σ = 34788072. Its totient is φ = 33206712.

The previous prime is 33997387. The next prime is 33997409. The reversal of 33997391 is 19379933.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 19379933 = 47 ⋅412339.

It is a cyclic number.

It is not a de Polignac number, because 33997391 - 2² = 33997387 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (33997321) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 395276 + ... + 395361.

It is an arithmetic number, because the mean of its divisors is an integer number (8697018).

Almost surely, 2^33997391 is an apocalyptic number.

33997391 is a deficient number, since it is larger than the sum of its proper divisors (790681).

33997391 is an equidigital number, since it uses as much as digits as its factorization.

33997391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 790680.

The product of its digits is 137781, while the sum is 44.

The square root of 33997391 is about 5830.7281706490. The cubic root of 33997391 is about 323.9528934970.

The spelling of 33997391 in words is "thirty-three million, nine hundred ninety-seven thousand, three hundred ninety-one".