1811708985 has 16 divisors (see below), whose sum is σ = 2904649920. Its totient is φ = 964272960.

The previous prime is 1811708923. The next prime is 1811708993. The reversal of 1811708985 is 5898071181.

It is not a de Polignac number, because 1811708985 - 2²³ = 1803320377 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 115630 + ... + 130359.

It is an arithmetic number, because the mean of its divisors is an integer number (181540620).

Almost surely, 2^1811708985 is an apocalyptic number.

1811708985 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1811708985 is a deficient number, since it is larger than the sum of its proper divisors (1092940935).

1811708985 is a wasteful number, since it uses less digits than its factorization.

1811708985 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 246488.

The product of its (nonzero) digits is 161280, while the sum is 48.

The square root of 1811708985 is about 42564.1749009657. The cubic root of 1811708985 is about 1219.0723452947.

The spelling of 1811708985 in words is "one billion, eight hundred eleven million, seven hundred eight thousand, nine hundred eighty-five".