21523053106 has 16 divisors (see below), whose sum is σ = 33178028760. Its totient is φ = 10464076800.

The previous prime is 21523053089. The next prime is 21523053107. The reversal of 21523053106 is 60135032512.

It can be written as a sum of positive squares in 4 ways, for example, as 21490094025 + 32959081 = 146595^2 + 5741^2 .

It is not an unprimeable number, because it can be changed into a prime (21523053107) 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, 27640 + ... + 209308.

Almost surely, 2^21523053106 is an apocalyptic number.

21523053106 is a deficient number, since it is larger than the sum of its proper divisors (11654975654).

21523053106 is a wasteful number, since it uses less digits than its factorization.

21523053106 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 183309.

The product of its (nonzero) digits is 5400, while the sum is 28.

Adding to 21523053106 its reverse (60135032512), we get a palindrome (81658085618).

The spelling of 21523053106 in words is "twenty-one billion, five hundred twenty-three million, fifty-three thousand, one hundred six".