21522014225 has 6 divisors (see below), whose sum is σ = 26687297670. Its totient is φ = 17217611360.

The previous prime is 21522014219. The next prime is 21522014243. The reversal of 21522014225 is 52241022512.

It can be written as a sum of positive squares in 3 ways, for example, as 4131789841 + 17390224384 = 64279^2 + 131872^2 .

It is not a de Polignac number, because 21522014225 - 2⁸ = 21522013969 is a prime.

It is a super-2 number, since 2×21522014225² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21522014194 and 21522014203.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 430440260 + ... + 430440309.

It is an arithmetic number, because the mean of its divisors is an integer number (4447882945).

Almost surely, 2^21522014225 is an apocalyptic number.

21522014225 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21522014225 is a deficient number, since it is larger than the sum of its proper divisors (5165283445).

21522014225 is an equidigital number, since it uses as much as digits as its factorization.

21522014225 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 860880579 (or 860880574 counting only the distinct ones).

The product of its (nonzero) digits is 3200, while the sum is 26.

Adding to 21522014225 its reverse (52241022512), we get a palindrome (73763036737).

The spelling of 21522014225 in words is "twenty-one billion, five hundred twenty-two million, fourteen thousand, two hundred twenty-five".