25663655321 has 8 divisors (see below), whose sum is σ = 26159133000. Its totient is φ = 25170589440.

The previous prime is 25663655291. The next prime is 25663655351. The reversal of 25663655321 is 12355636652.

It is an interprime number because it is at equal distance from previous prime (25663655291) and next prime (25663655351).

It can be written as a sum of positive squares in 4 ways, for example, as 319015321 + 25344640000 = 17861^2 + 159200^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 25663655321 - 2²² = 25659461017 is a prime.

It is a super-2 number, since 2×25663655321² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (25663655351) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 581456 + ... + 624033.

It is an arithmetic number, because the mean of its divisors is an integer number (3269891625).

Almost surely, 2^25663655321 is an apocalyptic number.

It is an amenable number.

25663655321 is a deficient number, since it is larger than the sum of its proper divisors (495477679).

25663655321 is a wasteful number, since it uses less digits than its factorization.

25663655321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1205899.

The product of its digits is 972000, while the sum is 44.

The spelling of 25663655321 in words is "twenty-five billion, six hundred sixty-three million, six hundred fifty-five thousand, three hundred twenty-one".