18019851 has 16 divisors (see below), whose sum is σ = 25054464. Its totient is φ = 11509344.

The previous prime is 18019849. The next prime is 18019861. The reversal of 18019851 is 15891081.

It is not a de Polignac number, because 18019851 - 2¹ = 18019849 is a prime.

It is not an unprimeable number, because it can be changed into a prime (18019861) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6226 + ... + 8648.

It is an arithmetic number, because the mean of its divisors is an integer number (1565904).

Almost surely, 2^18019851 is an apocalyptic number.

18019851 is a deficient number, since it is larger than the sum of its proper divisors (7034613).

18019851 is a wasteful number, since it uses less digits than its factorization.

18019851 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2530.

The product of its (nonzero) digits is 2880, while the sum is 33.

The square root of 18019851 is about 4244.9795052509. The cubic root of 18019851 is about 262.1704453920.

The spelling of 18019851 in words is "eighteen million, nineteen thousand, eight hundred fifty-one".