20218851 has 12 divisors (see below), whose sum is σ = 30147520. Its totient is φ = 13044240.

The previous prime is 20218843. The next prime is 20218859. The reversal of 20218851 is 15881202.

It is an interprime number because it is at equal distance from previous prime (20218843) and next prime (20218859).

It is not a de Polignac number, because 20218851 - 2³ = 20218843 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20218859) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 35956 + ... + 36513.

Almost surely, 2^20218851 is an apocalyptic number.

20218851 is a deficient number, since it is larger than the sum of its proper divisors (9928669).

20218851 is a wasteful number, since it uses less digits than its factorization.

20218851 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 72506 (or 72503 counting only the distinct ones).

The product of its (nonzero) digits is 1280, while the sum is 27.

The square root of 20218851 is about 4496.5376680286. The cubic root of 20218851 is about 272.4282604407.

The spelling of 20218851 in words is "twenty million, two hundred eighteen thousand, eight hundred fifty-one".