33891989 has 4 divisors (see below), whose sum is σ = 33903660. Its totient is φ = 33880320.

The previous prime is 33891973. The next prime is 33892009. The reversal of 33891989 is 98919833.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 21003889 + 12888100 = 4583^2 + 3590^2 .

It is a cyclic number.

It is not a de Polignac number, because 33891989 - 2⁴ = 33891973 is a prime.

It is a super-2 number, since 2×33891989² = 2297333836752242, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (33891919) 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, 2327 + ... + 8555.

It is an arithmetic number, because the mean of its divisors is an integer number (8475915).

Almost surely, 2^33891989 is an apocalyptic number.

It is an amenable number.

33891989 is a deficient number, since it is larger than the sum of its proper divisors (11671).

33891989 is an equidigital number, since it uses as much as digits as its factorization.

33891989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11670.

The product of its digits is 419904, while the sum is 50.

The square root of 33891989 is about 5821.6826605372. The cubic root of 33891989 is about 323.6177635589.

The spelling of 33891989 in words is "thirty-three million, eight hundred ninety-one thousand, nine hundred eighty-nine".