1801881081 has 48 divisors (see below), whose sum is σ = 3494574720. Its totient is φ = 864034560.

The previous prime is 1801881077. The next prime is 1801881101.

1801881081 is nontrivially palindromic in base 10.

It is not a de Polignac number, because 1801881081 - 2² = 1801881077 is a prime.

It is a super-2 number, since 2×1801881081² = 6493550860131457122, which contains 22 as substring.

1801881081 is a strobogrammatic number because it is the same when read upside-down.

1801881081 is a modest number, since divided by 81081 gives 18018 as remainder.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (1801881481) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 90996 + ... + 109013.

It is an arithmetic number, because the mean of its divisors is an integer number (72803640).

Almost surely, 2^1801881081 is an apocalyptic number.

1801881081 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1801881081 is a deficient number, since it is larger than the sum of its proper divisors (1692693639).

1801881081 is a wasteful number, since it uses less digits than its factorization.

1801881081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 200046 (or 200043 counting only the distinct ones).

The product of its (nonzero) digits is 4096, while the sum is 36.

The square root of 1801881081 is about 42448.5698345657. The cubic root of 1801881081 is about 1216.8639965751.

It can be divided in two parts, 18018 and 81081, that added together give a palindrome (99099).

The spelling of 1801881081 in words is "one billion, eight hundred one million, eight hundred eighty-one thousand, eighty-one".