66218361 has 16 divisors (see below), whose sum is σ = 96938688. Its totient is φ = 39873600.

The previous prime is 66218351. The next prime is 66218377. The reversal of 66218361 is 16381266.

It is not a de Polignac number, because 66218361 - 2⁵ = 66218329 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (66218351) 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, 1210 + ... + 11571.

It is an arithmetic number, because the mean of its divisors is an integer number (6058668).

Almost surely, 2^66218361 is an apocalyptic number.

It is an amenable number.

66218361 is a deficient number, since it is larger than the sum of its proper divisors (30720327).

66218361 is a wasteful number, since it uses less digits than its factorization.

66218361 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12952.

The product of its digits is 10368, while the sum is 33.

The square root of 66218361 is about 8137.4664976269. The cubic root of 66218361 is about 404.5691928716.

The spelling of 66218361 in words is "sixty-six million, two hundred eighteen thousand, three hundred sixty-one".