21617569331953 has 16 divisors (see below), whose sum is σ = 26159664991104. Its totient is φ = 17438990664960.

The previous prime is 21617569331843. The next prime is 21617569331971. The reversal of 21617569331953 is 35913396571612.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 21617569331953 - 2¹³ = 21617569323761 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21617569331891 and 21617569331900.

It is not an unprimeable number, because it can be changed into a prime (21617569331753) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3314743 + ... + 7363603.

It is an arithmetic number, because the mean of its divisors is an integer number (1634979061944).

Almost surely, 2^{21617569331953} is an apocalyptic number.

It is an amenable number.

21617569331953 is a deficient number, since it is larger than the sum of its proper divisors (4542095659151).

21617569331953 is a wasteful number, since it uses less digits than its factorization.

21617569331953 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4093752.

The product of its digits is 27556200, while the sum is 61.

The spelling of 21617569331953 in words is "twenty-one trillion, six hundred seventeen billion, five hundred sixty-nine million, three hundred thirty-one thousand, nine hundred fifty-three".