25415320221 has 24 divisors (see below), whose sum is σ = 36952263296. Its totient is φ = 16832448000.

The previous prime is 25415320213. The next prime is 25415320241. The reversal of 25415320221 is 12202351452.

25415320221 is a `hidden beast` number, since 2 + 5 + 415 + 3 + 20 + 221 = 666.

It is not a de Polignac number, because 25415320221 - 2³ = 25415320213 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 (25415320241) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1294746 + ... + 1314228.

Almost surely, 2^25415320221 is an apocalyptic number.

It is an amenable number.

25415320221 is a deficient number, since it is larger than the sum of its proper divisors (11536943075).

25415320221 is a wasteful number, since it uses less digits than its factorization.

25415320221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20433 (or 20430 counting only the distinct ones).

The product of its (nonzero) digits is 4800, while the sum is 27.

Adding to 25415320221 its reverse (12202351452), we get a palindrome (37617671673).

The spelling of 25415320221 in words is "twenty-five billion, four hundred fifteen million, three hundred twenty thousand, two hundred twenty-one".