65721321444 has 24 divisors (see below), whose sum is σ = 153392178240. Its totient is φ = 21901045984.

The previous prime is 65721321443. The next prime is 65721321467. The reversal of 65721321444 is 44412312756.

It is not an unprimeable number, because it can be changed into a prime (65721321443) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 712359 + ... + 799310.

It is an arithmetic number, because the mean of its divisors is an integer number (6391340760).

Almost surely, 2^65721321444 is an apocalyptic number.

It is an amenable number.

65721321444 is an abundant number, since it is smaller than the sum of its proper divisors (87670856796).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

65721321444 is a wasteful number, since it uses less digits than its factorization.

65721321444 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1515299 (or 1515297 counting only the distinct ones).

The product of its digits is 161280, while the sum is 39.

The spelling of 65721321444 in words is "sixty-five billion, seven hundred twenty-one million, three hundred twenty-one thousand, four hundred forty-four".