21265652401 has 8 divisors (see below), whose sum is σ = 24645907584. Its totient is φ = 17970973440.

The previous prime is 21265652377. The next prime is 21265652407. The reversal of 21265652401 is 10425656212.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21265652401 - 2²¹ = 21263555249 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21265652407) 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, 21393520 + ... + 21394513.

It is an arithmetic number, because the mean of its divisors is an integer number (3080738448).

Almost surely, 2^21265652401 is an apocalyptic number.

It is an amenable number.

21265652401 is a deficient number, since it is larger than the sum of its proper divisors (3380255183).

21265652401 is an equidigital number, since it uses as much as digits as its factorization.

21265652401 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42788111.

The product of its (nonzero) digits is 28800, while the sum is 34.

The spelling of 21265652401 in words is "twenty-one billion, two hundred sixty-five million, six hundred fifty-two thousand, four hundred one".