21115653353253 has 24 divisors (see below), whose sum is σ = 32512072694400. Its totient is φ = 13167389424384.

The previous prime is 21115653353243. The next prime is 21115653353281. The reversal of 21115653353253 is 35235335651112.

21115653353253 is a `hidden beast` number, since 2 + 1 + 1 + 1 + 5 + 65 + 3 + 3 + 532 + 53 = 666.

It is not a de Polignac number, because 21115653353253 - 2⁶ = 21115653353189 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 21115653353199 and 21115653353208.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21115653353203) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 781526700 + ... + 781553717.

It is an arithmetic number, because the mean of its divisors is an integer number (1354669695600).

Almost surely, 2^{21115653353253} is an apocalyptic number.

It is an amenable number.

21115653353253 is a deficient number, since it is larger than the sum of its proper divisors (11396419341147).

21115653353253 is a wasteful number, since it uses less digits than its factorization.

21115653353253 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1563080521 (or 1563080518 counting only the distinct ones).

The product of its digits is 1215000, while the sum is 45.

The spelling of 21115653353253 in words is "twenty-one trillion, one hundred fifteen billion, six hundred fifty-three million, three hundred fifty-three thousand, two hundred fifty-three".