1854808993 has 2 divisors, whose sum is σ = 1854808994. Its totient is φ = 1854808992.

The previous prime is 1854808939. The next prime is 1854809003. The reversal of 1854808993 is 3998084581.

Together with previous prime (1854808939) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1776875409 + 77933584 = 42153^2 + 8828^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1854808993 is a prime.

It is not a weakly prime, because it can be changed into another prime (1854808393) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 927404496 + 927404497.

It is an arithmetic number, because the mean of its divisors is an integer number (927404497).

Almost surely, 2^1854808993 is an apocalyptic number.

It is an amenable number.

1854808993 is a deficient number, since it is larger than the sum of its proper divisors (1).

1854808993 is an equidigital number, since it uses as much as digits as its factorization.

1854808993 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2488320, while the sum is 55.

The square root of 1854808993 is about 43067.4934608458. The cubic root of 1854808993 is about 1228.6638039938.

The spelling of 1854808993 in words is "one billion, eight hundred fifty-four million, eight hundred eight thousand, nine hundred ninety-three".