20218151 has 6 divisors (see below), whose sum is σ = 21477720. Its totient is φ = 19028576.

The previous prime is 20218141. The next prime is 20218183. The reversal of 20218151 is 15181202.

It is a happy number.

It is not a de Polignac number, because 20218151 - 2¹⁴ = 20201767 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20218141) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 34691 + ... + 35268.

It is an arithmetic number, because the mean of its divisors is an integer number (3579620).

Almost surely, 2^20218151 is an apocalyptic number.

20218151 is a deficient number, since it is larger than the sum of its proper divisors (1259569).

20218151 is an equidigital number, since it uses as much as digits as its factorization.

20218151 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 69993 (or 69976 counting only the distinct ones).

The product of its (nonzero) digits is 160, while the sum is 20.

The square root of 20218151 is about 4496.4598296882. The cubic root of 20218151 is about 272.4251164773.

Adding to 20218151 its reverse (15181202), we get a palindrome (35399353).

The spelling of 20218151 in words is "twenty million, two hundred eighteen thousand, one hundred fifty-one".