21726465201 has 27 divisors (see below), whose sum is σ = 36511575321. Its totient is φ = 12413354184.

The previous prime is 21726465191. The next prime is 21726465259. The reversal of 21726465201 is 10256462712.

It is a happy number.

The square root of 21726465201 is 147399.

It is a perfect power (a square), and thus also a powerful number.

21726465201 is a `hidden beast` number, since 2 + 1 + 7 + 2 + 646 + 5 + 2 + 0 + 1 = 666.

It is not a de Polignac number, because 21726465201 - 2⁷ = 21726465073 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21726465281) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 3091870 + ... + 3098888.

Almost surely, 2^21726465201 is an apocalyptic number.

21726465201 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

21726465201 is the 147399-th square number.

21726465201 is the 73700-th centered octagonal number.

It is an amenable number.

21726465201 is a deficient number, since it is larger than the sum of its proper divisors (14785110120).

21726465201 is an frugal number, since it uses more digits than its factorization.

21726465201 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14058 (or 7029 counting only the distinct ones).

The product of its (nonzero) digits is 40320, while the sum is 36.

Multiplying 21726465201 by its sum of digits (36), we get a square (782152747236 = 884394²).

The spelling of 21726465201 in words is "twenty-one billion, seven hundred twenty-six million, four hundred sixty-five thousand, two hundred one".