1806748991 has 4 divisors (see below), whose sum is σ = 1813465800. Its totient is φ = 1800032184.

The previous prime is 1806748939. The next prime is 1806749003. The reversal of 1806748991 is 1998476081.

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

It is a cyclic number.

It is not a de Polignac number, because 1806748991 - 2¹⁰ = 1806747967 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1806748891) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3358001 + ... + 3358538.

It is an arithmetic number, because the mean of its divisors is an integer number (453366450).

Almost surely, 2^1806748991 is an apocalyptic number.

1806748991 is a deficient number, since it is larger than the sum of its proper divisors (6716809).

1806748991 is an equidigital number, since it uses as much as digits as its factorization.

1806748991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6716808.

The product of its (nonzero) digits is 870912, while the sum is 53.

The square root of 1806748991 is about 42505.8700769670. The cubic root of 1806748991 is about 1217.9588261476.

The spelling of 1806748991 in words is "one billion, eight hundred six million, seven hundred forty-eight thousand, nine hundred ninety-one".