25000415521 has 2 divisors, whose sum is σ = 25000415522. Its totient is φ = 25000415520.

The previous prime is 25000415519. The next prime is 25000415537. The reversal of 25000415521 is 12551400052.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 22608129600 + 2392285921 = 150360^2 + 48911^2 .

It is a cyclic number.

It is not a de Polignac number, because 25000415521 - 2¹ = 25000415519 is a prime.

Together with 25000415519, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (25000415581) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12500207760 + 12500207761.

It is an arithmetic number, because the mean of its divisors is an integer number (12500207761).

Almost surely, 2^25000415521 is an apocalyptic number.

It is an amenable number.

25000415521 is a deficient number, since it is larger than the sum of its proper divisors (1).

25000415521 is an equidigital number, since it uses as much as digits as its factorization.

25000415521 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2000, while the sum is 25.

Adding to 25000415521 its reverse (12551400052), we get a palindrome (37551815573).

The spelling of 25000415521 in words is "twenty-five billion, four hundred fifteen thousand, five hundred twenty-one".