1821749811 has 96 divisors (see below), whose sum is σ = 3110515200. Its totient is φ = 926069760.

The previous prime is 1821749789. The next prime is 1821749837. The reversal of 1821749811 is 1189471281.

1821749811 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 1821749811 - 2⁵ = 1821749779 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1821749861) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 20469055 + ... + 20469143.

It is an arithmetic number, because the mean of its divisors is an integer number (32401200).

Almost surely, 2^1821749811 is an apocalyptic number.

1821749811 is a deficient number, since it is larger than the sum of its proper divisors (1288765389).

1821749811 is a wasteful number, since it uses less digits than its factorization.

1821749811 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 237 (or 208 counting only the distinct ones).

The product of its digits is 32256, while the sum is 42.

The square root of 1821749811 is about 42681.9611897110. The cubic root of 1821749811 is about 1221.3203055991.

The spelling of 1821749811 in words is "one billion, eight hundred twenty-one million, seven hundred forty-nine thousand, eight hundred eleven".