21106513253 has 8 divisors (see below), whose sum is σ = 24145363200. Its totient is φ = 18073571760.

The previous prime is 21106513237. The next prime is 21106513271. The reversal of 21106513253 is 35231560112.

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 21106513253 - 2⁴ = 21106513237 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21106513273) 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, 1469453 + ... + 1483746.

It is an arithmetic number, because the mean of its divisors is an integer number (3018170400).

Almost surely, 2^21106513253 is an apocalyptic number.

It is an amenable number.

21106513253 is a deficient number, since it is larger than the sum of its proper divisors (3038849947).

21106513253 is a wasteful number, since it uses less digits than its factorization.

21106513253 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2954227.

The product of its (nonzero) digits is 5400, while the sum is 29.

The spelling of 21106513253 in words is "twenty-one billion, one hundred six million, five hundred thirteen thousand, two hundred fifty-three".