21415254625 has 16 divisors (see below), whose sum is σ = 26792949456. Its totient is φ = 17089440000.

The previous prime is 21415254593. The next prime is 21415254631. The reversal of 21415254625 is 52645251412.

It can be written as a sum of positive squares in 8 ways, for example, as 286015744 + 21129238881 = 16912^2 + 145359^2 .

It is not a de Polignac number, because 21415254625 - 2⁵ = 21415254593 is a prime.

It is a super-2 number, since 2×21415254625² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

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 15 ways as a sum of consecutive naturals, for example, 163494 + ... + 263743.

It is an arithmetic number, because the mean of its divisors is an integer number (1674559341).

Almost surely, 2^21415254625 is an apocalyptic number.

21415254625 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21415254625 is a deficient number, since it is larger than the sum of its proper divisors (5377694831).

21415254625 is an equidigital number, since it uses as much as digits as its factorization.

21415254625 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 427653 (or 427643 counting only the distinct ones).

The product of its digits is 96000, while the sum is 37.

The spelling of 21415254625 in words is "twenty-one billion, four hundred fifteen million, two hundred fifty-four thousand, six hundred twenty-five".