21222765653 has 4 divisors (see below), whose sum is σ = 21237393408. Its totient is φ = 21208137900.

The previous prime is 21222765647. The next prime is 21222765691. The reversal of 21222765653 is 35656722212.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21222765653 - 2¹⁸ = 21222503509 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21222765653.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21222765853) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7311701 + ... + 7314602.

It is an arithmetic number, because the mean of its divisors is an integer number (5309348352).

Almost surely, 2^21222765653 is an apocalyptic number.

It is an amenable number.

21222765653 is a deficient number, since it is larger than the sum of its proper divisors (14627755).

21222765653 is a wasteful number, since it uses less digits than its factorization.

21222765653 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14627754.

The product of its digits is 302400, while the sum is 41.

The spelling of 21222765653 in words is "twenty-one billion, two hundred twenty-two million, seven hundred sixty-five thousand, six hundred fifty-three".