1806290945 has 4 divisors (see below), whose sum is σ = 2167549140. Its totient is φ = 1445032752.

The previous prime is 1806290923. The next prime is 1806290951. The reversal of 1806290945 is 5490926081.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 628153969 + 1178136976 = 25063^2 + 34324^2 .

It is a cyclic number.

It is not a de Polignac number, because 1806290945 - 2¹⁰ = 1806289921 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1806290896 and 1806290905.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 180629090 + ... + 180629099.

It is an arithmetic number, because the mean of its divisors is an integer number (541887285).

Almost surely, 2^1806290945 is an apocalyptic number.

It is an amenable number.

1806290945 is a deficient number, since it is larger than the sum of its proper divisors (361258195).

1806290945 is an equidigital number, since it uses as much as digits as its factorization.

1806290945 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 361258194.

The product of its (nonzero) digits is 155520, while the sum is 44.

The square root of 1806290945 is about 42500.4817031525. The cubic root of 1806290945 is about 1217.8558920337.

The spelling of 1806290945 in words is "one billion, eight hundred six million, two hundred ninety thousand, nine hundred forty-five".