33868137721 has 16 divisors (see below), whose sum is σ = 38597666688. Its totient is φ = 29416780800.

The previous prime is 33868137703. The next prime is 33868137727. The reversal of 33868137721 is 12773186833.

It is not a de Polignac number, because 33868137721 - 2¹⁹ = 33867613433 is a prime.

It is a super-2 number, since 2×33868137721² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (33868137727) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 145561 + ... + 298201.

It is an arithmetic number, because the mean of its divisors is an integer number (2412354168).

Almost surely, 2^33868137721 is an apocalyptic number.

It is an amenable number.

33868137721 is a deficient number, since it is larger than the sum of its proper divisors (4729528967).

33868137721 is a wasteful number, since it uses less digits than its factorization.

33868137721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 153552.

The product of its digits is 1016064, while the sum is 49.

The spelling of 33868137721 in words is "thirty-three billion, eight hundred sixty-eight million, one hundred thirty-seven thousand, seven hundred twenty-one".