21448729364 has 12 divisors (see below), whose sum is σ = 37578082164. Its totient is φ = 10712134464.

The previous prime is 21448729361. The next prime is 21448729397. The reversal of 21448729364 is 46392784412.

It can be written as a sum of positive squares in 2 ways, for example, as 8969605264 + 12479124100 = 94708^2 + 111710^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21448729361) 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, 3053609 + ... + 3060624.

It is an arithmetic number, because the mean of its divisors is an integer number (3131506847).

Almost surely, 2^21448729364 is an apocalyptic number.

It is an amenable number.

21448729364 is a deficient number, since it is larger than the sum of its proper divisors (16129352800).

21448729364 is a wasteful number, since it uses less digits than its factorization.

21448729364 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6115114 (or 6115112 counting only the distinct ones).

The product of its digits is 2322432, while the sum is 50.

The spelling of 21448729364 in words is "twenty-one billion, four hundred forty-eight million, seven hundred twenty-nine thousand, three hundred sixty-four".