21726564470547 has 16 divisors (see below), whose sum is σ = 29460287969280. Its totient is φ = 14238617635232.

The previous prime is 21726564470537. The next prime is 21726564470551. The reversal of 21726564470547 is 74507446562712.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 21726564470547 - 2¹⁸ = 21726564208403 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21726564470537) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 8815438 + ... + 11007500.

It is an arithmetic number, because the mean of its divisors is an integer number (1841267998080).

Almost surely, 2^{21726564470547} is an apocalyptic number.

21726564470547 is a deficient number, since it is larger than the sum of its proper divisors (7733723498733).

21726564470547 is a wasteful number, since it uses less digits than its factorization.

21726564470547 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2248122.

The product of its (nonzero) digits is 79027200, while the sum is 60.

The spelling of 21726564470547 in words is "twenty-one trillion, seven hundred twenty-six billion, five hundred sixty-four million, four hundred seventy thousand, five hundred forty-seven".