33281980721 has 4 divisors (see below), whose sum is σ = 36307615344. Its totient is φ = 30256346100.

The previous prime is 33281980679. The next prime is 33281980723. The reversal of 33281980721 is 12708918233.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 33281980721 - 2⁶ = 33281980657 is a prime.

It is a super-2 number, since 2×33281980721² (a number of 22 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (33281980723) 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, 1512817295 + ... + 1512817316.

It is an arithmetic number, because the mean of its divisors is an integer number (9076903836).

Almost surely, 2^33281980721 is an apocalyptic number.

It is an amenable number.

33281980721 is a deficient number, since it is larger than the sum of its proper divisors (3025634623).

33281980721 is a wasteful number, since it uses less digits than its factorization.

33281980721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3025634622.

The product of its (nonzero) digits is 145152, while the sum is 44.

The spelling of 33281980721 in words is "thirty-three billion, two hundred eighty-one million, nine hundred eighty thousand, seven hundred twenty-one".