66364551 has 12 divisors (see below), whose sum is σ = 104574600. Its totient is φ = 40220880.

The previous prime is 66364547. The next prime is 66364553. The reversal of 66364551 is 15546366.

66364551 is a `hidden beast` number, since 6 + 6 + 3 + 645 + 5 + 1 = 666.

It is not a de Polignac number, because 66364551 - 2² = 66364547 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66364553) 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, 335076 + ... + 335273.

It is an arithmetic number, because the mean of its divisors is an integer number (8714550).

Almost surely, 2^66364551 is an apocalyptic number.

66364551 is a deficient number, since it is larger than the sum of its proper divisors (38210049).

66364551 is a wasteful number, since it uses less digits than its factorization.

66364551 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 670366 (or 670363 counting only the distinct ones).

The product of its digits is 64800, while the sum is 36.

The square root of 66364551 is about 8146.4440708815. Note that the first 3 decimals coincide. The cubic root of 66364551 is about 404.8666959546.

The spelling of 66364551 in words is "sixty-six million, three hundred sixty-four thousand, five hundred fifty-one".