21644153202 has 32 divisors (see below), whose sum is σ = 52076160000. Its totient is φ = 5858567568.

The previous prime is 21644153191. The next prime is 21644153233. The reversal of 21644153202 is 20235144612.

It is a self number, because there is not a number n which added to its sum of digits gives 21644153202.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 13560702 + ... + 13562297.

It is an arithmetic number, because the mean of its divisors is an integer number (1627380000).

Almost surely, 2^21644153202 is an apocalyptic number.

21644153202 is an abundant number, since it is smaller than the sum of its proper divisors (30432006798).

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

21644153202 is a wasteful number, since it uses less digits than its factorization.

21644153202 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27123030.

The product of its (nonzero) digits is 11520, while the sum is 30.

Adding to 21644153202 its reverse (20235144612), we get a palindrome (41879297814).

The spelling of 21644153202 in words is "twenty-one billion, six hundred forty-four million, one hundred fifty-three thousand, two hundred two".