18920811 has 24 divisors (see below), whose sum is σ = 31607184. Its totient is φ = 9979200.

The previous prime is 18920809. The next prime is 18920821. The reversal of 18920811 is 11802981.

It is not a de Polignac number, because 18920811 - 2¹ = 18920809 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18920821) 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, 3040 + ... + 6861.

It is an arithmetic number, because the mean of its divisors is an integer number (1316966).

Almost surely, 2^18920811 is an apocalyptic number.

18920811 is a deficient number, since it is larger than the sum of its proper divisors (12686373).

18920811 is a wasteful number, since it uses less digits than its factorization.

18920811 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9931 (or 9924 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 30.

The square root of 18920811 is about 4349.8058577366. The cubic root of 18920811 is about 266.4689327564.

The spelling of 18920811 in words is "eighteen million, nine hundred twenty thousand, eight hundred eleven".