33521372921 has 2 divisors, whose sum is σ = 33521372922. Its totient is φ = 33521372920.

The previous prime is 33521372891. The next prime is 33521372993. The reversal of 33521372921 is 12927312533.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 27270889321 + 6250483600 = 165139^2 + 79060^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-33521372921 is a prime.

It is a super-2 number, since 2×33521372921² (a number of 22 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (33521377921) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 16760686460 + 16760686461.

It is an arithmetic number, because the mean of its divisors is an integer number (16760686461).

Almost surely, 2^33521372921 is an apocalyptic number.

It is an amenable number.

33521372921 is a deficient number, since it is larger than the sum of its proper divisors (1).

33521372921 is an equidigital number, since it uses as much as digits as its factorization.

33521372921 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 68040, while the sum is 38.

The spelling of 33521372921 in words is "thirty-three billion, five hundred twenty-one million, three hundred seventy-two thousand, nine hundred twenty-one".