21472506225 has 27 divisors (see below), whose sum is σ = 38463581793. Its totient is φ = 11450831040.

The previous prime is 21472506203. The next prime is 21472506229. The reversal of 21472506225 is 52260527412.

The square root of 21472506225 is 146535.

It is a perfect power (a square), and thus also a powerful number.

21472506225 is a `hidden beast` number, since 2 + 1 + 4 + 7 + 25 + 0 + 622 + 5 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 1898257761 + 19574248464 = 43569^2 + 139908^2 .

It is not a de Polignac number, because 21472506225 - 2²¹ = 21470409073 is a prime.

It is a super-2 number, since 2×21472506225² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21472506225.

It is not an unprimeable number, because it can be changed into a prime (21472506229) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 2193141 + ... + 2202909.

Almost surely, 2^21472506225 is an apocalyptic number.

21472506225 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

21472506225 is the 146535-th square number.

21472506225 is the 73268-th centered octagonal number.

It is an amenable number.

21472506225 is a deficient number, since it is larger than the sum of its proper divisors (16991075568).

21472506225 is an frugal number, since it uses more digits than its factorization.

21472506225 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19554 (or 9777 counting only the distinct ones).

The product of its (nonzero) digits is 67200, while the sum is 36.

Multiplying 21472506225 by its sum of digits (36), we get a square (773010224100 = 879210²).

The spelling of 21472506225 in words is "twenty-one billion, four hundred seventy-two million, five hundred six thousand, two hundred twenty-five".