2551643894 has 16 divisors (see below), whose sum is σ = 3860444016. Its totient is φ = 1264876800.

The previous prime is 2551643867. The next prime is 2551643903. The reversal of 2551643894 is 4983461552.

It is a super-5 number, since 5×2551643894⁵ (a number of 48 digits) contains 55555 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 97754 + ... + 121074.

It is an arithmetic number, because the mean of its divisors is an integer number (241277751).

Almost surely, 2^2551643894 is an apocalyptic number.

2551643894 is a deficient number, since it is larger than the sum of its proper divisors (1308800122).

2551643894 is a wasteful number, since it uses less digits than its factorization.

2551643894 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23791.

The product of its digits is 1036800, while the sum is 47.

The square root of 2551643894 is about 50513.7990454094. The cubic root of 2551643894 is about 1366.4907245116.

The spelling of 2551643894 in words is "two billion, five hundred fifty-one million, six hundred forty-three thousand, eight hundred ninety-four".