21625244653 has 8 divisors (see below), whose sum is σ = 21923344440. Its totient is φ = 21328369920.

The previous prime is 21625244651. The next prime is 21625244671. The reversal of 21625244653 is 35644252612.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 8305924 + 21616938729 = 2882^2 + 147027^2 .

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 21625244653 - 2¹ = 21625244651 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21625244651) 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 7 ways as a sum of consecutive naturals, for example, 270688 + ... + 341353.

It is an arithmetic number, because the mean of its divisors is an integer number (2740418055).

Almost surely, 2^21625244653 is an apocalyptic number.

It is an amenable number.

21625244653 is a deficient number, since it is larger than the sum of its proper divisors (298099787).

21625244653 is an equidigital number, since it uses as much as digits as its factorization.

21625244653 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 612527.

The product of its digits is 345600, while the sum is 40.

The spelling of 21625244653 in words is "twenty-one billion, six hundred twenty-five million, two hundred forty-four thousand, six hundred fifty-three".