21222072536 has 64 divisors (see below), whose sum is σ = 49452379200. Its totient is φ = 8328794112.

The previous prime is 21222072511. The next prime is 21222072551. The reversal of 21222072536 is 63527022212.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 266021 + ... + 336468.

It is an arithmetic number, because the mean of its divisors is an integer number (772693425).

Almost surely, 2^21222072536 is an apocalyptic number.

It is an amenable number.

21222072536 is an abundant number, since it is smaller than the sum of its proper divisors (28230306664).

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

21222072536 is a wasteful number, since it uses less digits than its factorization.

21222072536 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 602556 (or 602552 counting only the distinct ones).

The product of its (nonzero) digits is 20160, while the sum is 32.

Adding to 21222072536 its reverse (63527022212), we get a palindrome (84749094748).

The spelling of 21222072536 in words is "twenty-one billion, two hundred twenty-two million, seventy-two thousand, five hundred thirty-six".