21642565411 has 8 divisors (see below), whose sum is σ = 23705853120. Its totient is φ = 19667077248.

The previous prime is 21642565397. The next prime is 21642565421. The reversal of 21642565411 is 11456524612.

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

It is a cyclic number.

It is not a de Polignac number, because 21642565411 - 2⁵ = 21642565379 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21642565421) 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, 21949371 + ... + 21950356.

It is an arithmetic number, because the mean of its divisors is an integer number (2963231640).

Almost surely, 2^21642565411 is an apocalyptic number.

21642565411 is a deficient number, since it is larger than the sum of its proper divisors (2063287709).

21642565411 is a wasteful number, since it uses less digits than its factorization.

21642565411 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43899773.

The product of its digits is 57600, while the sum is 37.

The spelling of 21642565411 in words is "twenty-one billion, six hundred forty-two million, five hundred sixty-five thousand, four hundred eleven".