21761454613553 has 4 divisors (see below), whose sum is σ = 21761631195888. Its totient is φ = 21761278031220.

The previous prime is 21761454613523. The next prime is 21761454613571. The reversal of 21761454613553 is 35531645416712.

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 21761454613553 - 2²² = 21761450419249 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21761454613495 and 21761454613504.

It is not an unprimeable number, because it can be changed into a prime (21761454613523) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 88106183 + ... + 88352828.

It is an arithmetic number, because the mean of its divisors is an integer number (5440407798972).

Almost surely, 2^{21761454613553} is an apocalyptic number.

It is an amenable number.

21761454613553 is a deficient number, since it is larger than the sum of its proper divisors (176582335).

21761454613553 is a wasteful number, since it uses less digits than its factorization.

21761454613553 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 176582334.

The product of its digits is 9072000, while the sum is 53.

The spelling of 21761454613553 in words is "twenty-one trillion, seven hundred sixty-one billion, four hundred fifty-four million, six hundred thirteen thousand, five hundred fifty-three".