1855388161 has 16 divisors (see below), whose sum is σ = 2110929408. Its totient is φ = 1615449600.

The previous prime is 1855388153. The next prime is 1855388167. The reversal of 1855388161 is 1618835581.

It is a cyclic number.

It is not a de Polignac number, because 1855388161 - 2³ = 1855388153 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1855388167) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5031 + ... + 61123.

It is an arithmetic number, because the mean of its divisors is an integer number (131933088).

Almost surely, 2^1855388161 is an apocalyptic number.

1855388161 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1855388161 is a deficient number, since it is larger than the sum of its proper divisors (255541247).

1855388161 is a wasteful number, since it uses less digits than its factorization.

1855388161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 56232.

The product of its digits is 230400, while the sum is 46.

The square root of 1855388161 is about 43074.2168936360. The cubic root of 1855388161 is about 1228.7916749690.

The spelling of 1855388161 in words is "one billion, eight hundred fifty-five million, three hundred eighty-eight thousand, one hundred sixty-one".