1820412081 has 24 divisors (see below), whose sum is σ = 2679579240. Its totient is φ = 1190592000.

The previous prime is 1820412047. The next prime is 1820412107. The reversal of 1820412081 is 1802140281.

It can be written as a sum of positive squares in 4 ways, for example, as 724471056 + 1095941025 = 26916^2 + 33105^2 .

It is not a de Polignac number, because 1820412081 - 2⁹ = 1820411569 is a prime.

It is a super-2 number, since 2×1820412081² = 6627800289301501122, which contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (1820412281) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 216015 + ... + 224283.

It is an arithmetic number, because the mean of its divisors is an integer number (111649135).

Almost surely, 2^1820412081 is an apocalyptic number.

It is an amenable number.

1820412081 is a deficient number, since it is larger than the sum of its proper divisors (859167159).

1820412081 is a wasteful number, since it uses less digits than its factorization.

1820412081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8737 (or 8734 counting only the distinct ones).

The product of its (nonzero) digits is 1024, while the sum is 27.

The square root of 1820412081 is about 42666.2874058665. The cubic root of 1820412081 is about 1221.0212896255.

The spelling of 1820412081 in words is "one billion, eight hundred twenty million, four hundred twelve thousand, eighty-one".