21975631225 has 6 divisors (see below), whose sum is σ = 27249782750. Its totient is φ = 17580504960.

The previous prime is 21975631219. The next prime is 21975631241. The reversal of 21975631225 is 52213657912.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 2961427561 + 19014203664 = 54419^2 + 137892^2 .

It is not a de Polignac number, because 21975631225 - 2¹⁷ = 21975500153 is a prime.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 439512600 + ... + 439512649.

Almost surely, 2^21975631225 is an apocalyptic number.

21975631225 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21975631225 is a deficient number, since it is larger than the sum of its proper divisors (5274151525).

21975631225 is an equidigital number, since it uses as much as digits as its factorization.

21975631225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 879025259 (or 879025254 counting only the distinct ones).

The product of its digits is 226800, while the sum is 43.

The spelling of 21975631225 in words is "twenty-one billion, nine hundred seventy-five million, six hundred thirty-one thousand, two hundred twenty-five".