21297885368 has 32 divisors (see below), whose sum is σ = 41725532160. Its totient is φ = 10172316000.

The previous prime is 21297885361. The next prime is 21297885377. The reversal of 21297885368 is 86358879212.

It is a super-2 number, since 2×21297885368² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21297885361) 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, 61121 + ... + 215247.

It is an arithmetic number, because the mean of its divisors is an integer number (1303922880).

Almost surely, 2^21297885368 is an apocalyptic number.

It is an amenable number.

21297885368 is a deficient number, since it is larger than the sum of its proper divisors (20427646792).

21297885368 is a wasteful number, since it uses less digits than its factorization.

21297885368 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 154907 (or 154903 counting only the distinct ones).

The product of its digits is 11612160, while the sum is 59.

The spelling of 21297885368 in words is "twenty-one billion, two hundred ninety-seven million, eight hundred eighty-five thousand, three hundred sixty-eight".