21764215711 has 16 divisors (see below), whose sum is σ = 26421258240. Its totient is φ = 17501201280.

The previous prime is 21764215673. The next prime is 21764215717. The reversal of 21764215711 is 11751246712.

It is a cyclic number.

It is not a de Polignac number, because 21764215711 - 2⁹ = 21764215199 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21764215717) 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, 257031 + ... + 331048.

It is an arithmetic number, because the mean of its divisors is an integer number (1651328640).

Almost surely, 2^21764215711 is an apocalyptic number.

21764215711 is a deficient number, since it is larger than the sum of its proper divisors (4657042529).

21764215711 is a wasteful number, since it uses less digits than its factorization.

21764215711 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 588414.

The product of its digits is 23520, while the sum is 37.

The spelling of 21764215711 in words is "twenty-one billion, seven hundred sixty-four million, two hundred fifteen thousand, seven hundred eleven".