1806556081 has 16 divisors (see below), whose sum is σ = 2093572800. Its totient is φ = 1541592000.

The previous prime is 1806556079. The next prime is 1806556099.

1806556081 is nontrivially palindromic in base 10.

It is a cyclic number.

It is not a de Polignac number, because 1806556081 - 2¹ = 1806556079 is a prime.

It is a super-2 number, since 2×1806556081² = 6527289747596157122, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1806556001) 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, 16870 + ... + 62431.

It is an arithmetic number, because the mean of its divisors is an integer number (130848300).

Almost surely, 2^1806556081 is an apocalyptic number.

1806556081 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1806556081 is a deficient number, since it is larger than the sum of its proper divisors (287016719).

1806556081 is a wasteful number, since it uses less digits than its factorization.

1806556081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 79440.

The product of its (nonzero) digits is 57600, while the sum is 40.

The square root of 1806556081 is about 42503.6008004028. The cubic root of 1806556081 is about 1217.9154766838.

The spelling of 1806556081 in words is "one billion, eight hundred six million, five hundred fifty-six thousand, eighty-one".