25415312125421 has 4 divisors (see below), whose sum is σ = 25421276765244. Its totient is φ = 25409347485600.

The previous prime is 25415312125393. The next prime is 25415312125481. The reversal of 25415312125421 is 12452121351452.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 19397735169796 + 6017576955625 = 4404286^2 + 2453075^2 .

It is a cyclic number.

It is not a de Polignac number, because 25415312125421 - 2¹⁴ = 25415312109037 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25415312125481) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2982313520 + ... + 2982322041.

It is an arithmetic number, because the mean of its divisors is an integer number (6355319191311).

Almost surely, 2^{25415312125421} is an apocalyptic number.

It is an amenable number.

25415312125421 is a deficient number, since it is larger than the sum of its proper divisors (5964639823).

25415312125421 is an equidigital number, since it uses as much as digits as its factorization.

25415312125421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5964639822.

The product of its digits is 96000, while the sum is 38.

Adding to 25415312125421 its reverse (12452121351452), we get a palindrome (37867433476873).

The spelling of 25415312125421 in words is "twenty-five trillion, four hundred fifteen billion, three hundred twelve million, one hundred twenty-five thousand, four hundred twenty-one".