21525223153 has 16 divisors (see below), whose sum is σ = 24709740160. Its totient is φ = 18368228736.

The previous prime is 21525223133. The next prime is 21525223189. The reversal of 21525223153 is 35132252512.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21525223153 is a prime.

It is a super-2 number, since 2×21525223153² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21525223123) 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, 1876351 + ... + 1887787.

It is an arithmetic number, because the mean of its divisors is an integer number (1544358760).

Almost surely, 2^21525223153 is an apocalyptic number.

It is an amenable number.

21525223153 is a deficient number, since it is larger than the sum of its proper divisors (3184517007).

21525223153 is a wasteful number, since it uses less digits than its factorization.

21525223153 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12616.

The product of its digits is 18000, while the sum is 31.

Adding to 21525223153 its reverse (35132252512), we get a palindrome (56657475665).

The spelling of 21525223153 in words is "twenty-one billion, five hundred twenty-five million, two hundred twenty-three thousand, one hundred fifty-three".