33243331981 has 2 divisors, whose sum is σ = 33243331982. Its totient is φ = 33243331980.

The previous prime is 33243331943. The next prime is 33243332029. The reversal of 33243331981 is 18913334233.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 29632523881 + 3610808100 = 172141^2 + 60090^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-33243331981 is a prime.

It is a super-2 number, since 2×33243331981² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (33243338981) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 16621665990 + 16621665991.

It is an arithmetic number, because the mean of its divisors is an integer number (16621665991).

Almost surely, 2^33243331981 is an apocalyptic number.

It is an amenable number.

33243331981 is a deficient number, since it is larger than the sum of its proper divisors (1).

33243331981 is an equidigital number, since it uses as much as digits as its factorization.

33243331981 is an evil number, because the sum of its binary digits is even.

The product of its digits is 139968, while the sum is 40.

The spelling of 33243331981 in words is "thirty-three billion, two hundred forty-three million, three hundred thirty-one thousand, nine hundred eighty-one".