18890778857 has 8 divisors (see below), whose sum is σ = 19135267200. Its totient is φ = 18646424784.

The previous prime is 18890778847. The next prime is 18890778859. The reversal of 18890778857 is 75887709881.

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 18890778857 - 2¹⁰ = 18890777833 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18890778859) by changing a digit.

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, 266903 + ... + 330179.

It is an arithmetic number, because the mean of its divisors is an integer number (2391908400).

Almost surely, 2^18890778857 is an apocalyptic number.

It is an amenable number.

18890778857 is a deficient number, since it is larger than the sum of its proper divisors (244488343).

18890778857 is an equidigital number, since it uses as much as digits as its factorization.

18890778857 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 67135.

The product of its (nonzero) digits is 63221760, while the sum is 68.

The spelling of 18890778857 in words is "eighteen billion, eight hundred ninety million, seven hundred seventy-eight thousand, eight hundred fifty-seven".