66224251 has 4 divisors (see below), whose sum is σ = 66265600. Its totient is φ = 66182904.

The previous prime is 66224243. The next prime is 66224261. The reversal of 66224251 is 15242266.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 66224251 - 2³ = 66224243 is a prime.

It is a super-2 number, since 2×66224251² = 8771302841022002, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66224201) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 18171 + ... + 21508.

It is an arithmetic number, because the mean of its divisors is an integer number (16566400).

Almost surely, 2^66224251 is an apocalyptic number.

66224251 is a deficient number, since it is larger than the sum of its proper divisors (41349).

66224251 is a wasteful number, since it uses less digits than its factorization.

66224251 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41348.

The product of its digits is 5760, while the sum is 28.

The square root of 66224251 is about 8137.8283958314. The cubic root of 66224251 is about 404.5811877416.

The spelling of 66224251 in words is "sixty-six million, two hundred twenty-four thousand, two hundred fifty-one".