21524211553 has 16 divisors (see below), whose sum is σ = 23264176320. Its totient is φ = 19796393664.

The previous prime is 21524211551. The next prime is 21524211571. The reversal of 21524211553 is 35511242512.

It is a cyclic number.

It is not a de Polignac number, because 21524211553 - 2¹ = 21524211551 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21524211551) 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, 9595050 + ... + 9597292.

It is an arithmetic number, because the mean of its divisors is an integer number (1454011020).

Almost surely, 2^21524211553 is an apocalyptic number.

It is an amenable number.

21524211553 is a deficient number, since it is larger than the sum of its proper divisors (1739964767).

21524211553 is a wasteful number, since it uses less digits than its factorization.

21524211553 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4608.

The product of its digits is 12000, while the sum is 31.

The spelling of 21524211553 in words is "twenty-one billion, five hundred twenty-four million, two hundred eleven thousand, five hundred fifty-three".