21552608693 has 36 divisors (see below), whose sum is σ = 27598448556. Its totient is φ = 16769491200.

The previous prime is 21552608657. The next prime is 21552608723. The reversal of 21552608693 is 39680625512.

It can be written as a sum of positive squares in 2 ways, for example, as 8810262769 + 12742345924 = 93863^2 + 112882^2 .

It is not a de Polignac number, because 21552608693 - 2⁸ = 21552608437 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21552608593) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 4723133 + ... + 4727693.

It is an arithmetic number, because the mean of its divisors is an integer number (766623571).

Almost surely, 2^21552608693 is an apocalyptic number.

It is an amenable number.

21552608693 is a deficient number, since it is larger than the sum of its proper divisors (6045839863).

21552608693 is a wasteful number, since it uses less digits than its factorization.

21552608693 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5394 (or 5376 counting only the distinct ones).

The product of its (nonzero) digits is 777600, while the sum is 47.

The spelling of 21552608693 in words is "twenty-one billion, five hundred fifty-two million, six hundred eight thousand, six hundred ninety-three".