21727248771 has 16 divisors (see below), whose sum is σ = 30567196800. Its totient is φ = 13689707328.

The previous prime is 21727248761. The next prime is 21727248787. The reversal of 21727248771 is 17784272712.

It is not a de Polignac number, because 21727248771 - 2¹⁵ = 21727216003 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21727248771.

It is not an unprimeable number, because it can be changed into a prime (21727248731) 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, 430986 + ... + 478751.

It is an arithmetic number, because the mean of its divisors is an integer number (1910449800).

Almost surely, 2^21727248771 is an apocalyptic number.

21727248771 is a deficient number, since it is larger than the sum of its proper divisors (8839948029).

21727248771 is a wasteful number, since it uses less digits than its factorization.

21727248771 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 910178.

The product of its digits is 614656, while the sum is 48.

The spelling of 21727248771 in words is "twenty-one billion, seven hundred twenty-seven million, two hundred forty-eight thousand, seven hundred seventy-one".