21515453520553 has 8 divisors (see below), whose sum is σ = 21520331078400. Its totient is φ = 21510576277008.

The previous prime is 21515453520521. The next prime is 21515453520577. The reversal of 21515453520553 is 35502535451512.

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 21515453520553 - 2⁵ = 21515453520521 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21515453520053) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 183750975 + ... + 183868027.

It is an arithmetic number, because the mean of its divisors is an integer number (2690041384800).

Almost surely, 2^{21515453520553} is an apocalyptic number.

It is an amenable number.

21515453520553 is a deficient number, since it is larger than the sum of its proper divisors (4877557847).

21515453520553 is a wasteful number, since it uses less digits than its factorization.

21515453520553 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 157151.

The product of its (nonzero) digits is 2250000, while the sum is 46.

The spelling of 21515453520553 in words is "twenty-one trillion, five hundred fifteen billion, four hundred fifty-three million, five hundred twenty thousand, five hundred fifty-three".