25551804321 has 16 divisors (see below), whose sum is σ = 40081262400. Its totient is φ = 16032504384.

The previous prime is 25551804277. The next prime is 25551804347. The reversal of 25551804321 is 12340815552.

25551804321 is a `hidden beast` number, since 2 + 5 + 551 + 80 + 4 + 3 + 21 = 666.

It is not a de Polignac number, because 25551804321 - 2¹¹ = 25551802273 is a prime.

It is not an unprimeable number, because it can be changed into a prime (25551804361) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 27833751 + ... + 27834668.

It is an arithmetic number, because the mean of its divisors is an integer number (2505078900).

Almost surely, 2^25551804321 is an apocalyptic number.

It is an amenable number.

25551804321 is a deficient number, since it is larger than the sum of its proper divisors (14529458079).

25551804321 is a wasteful number, since it uses less digits than its factorization.

25551804321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55668445 (or 55668439 counting only the distinct ones).

The product of its (nonzero) digits is 48000, while the sum is 36.

The spelling of 25551804321 in words is "twenty-five billion, five hundred fifty-one million, eight hundred four thousand, three hundred twenty-one".