21652542642 has 8 divisors (see below), whose sum is σ = 43305085296. Its totient is φ = 7217514212.

The previous prime is 21652542641. The next prime is 21652542647. The reversal of 21652542642 is 24624525612.

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

21652542642 is an admirable number.

It is a self number, because there is not a number n which added to its sum of digits gives 21652542642.

It is not an unprimeable number, because it can be changed into a prime (21652542641) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1804378548 + ... + 1804378559.

It is an arithmetic number, because the mean of its divisors is an integer number (5413135662).

Almost surely, 2^21652542642 is an apocalyptic number.

21652542642 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21652542642 is a wasteful number, since it uses less digits than its factorization.

21652542642 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3608757112.

The product of its digits is 230400, while the sum is 39.

The spelling of 21652542642 in words is "twenty-one billion, six hundred fifty-two million, five hundred forty-two thousand, six hundred forty-two".