33001661921 has 2 divisors, whose sum is σ = 33001661922. Its totient is φ = 33001661920.

The previous prime is 33001661899. The next prime is 33001661923. The reversal of 33001661921 is 12916610033.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 30770422225 + 2231239696 = 175415^2 + 47236^2 .

It is a cyclic number.

It is not a de Polignac number, because 33001661921 - 2²² = 32997467617 is a prime.

Together with 33001661923, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (33001661923) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 16500830960 + 16500830961.

It is an arithmetic number, because the mean of its divisors is an integer number (16500830961).

Almost surely, 2^33001661921 is an apocalyptic number.

It is an amenable number.

33001661921 is a deficient number, since it is larger than the sum of its proper divisors (1).

33001661921 is an equidigital number, since it uses as much as digits as its factorization.

33001661921 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5832, while the sum is 32.

The spelling of 33001661921 in words is "thirty-three billion, one million, six hundred sixty-one thousand, nine hundred twenty-one".