66654751 has 4 divisors (see below), whose sum is σ = 66689272. Its totient is φ = 66620232.

The previous prime is 66654737. The next prime is 66654779. The reversal of 66654751 is 15745666.

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 66654751 - 2⁹ = 66654239 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 (66654701) 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, 14181 + ... + 18286.

It is an arithmetic number, because the mean of its divisors is an integer number (16672318).

Almost surely, 2^66654751 is an apocalyptic number.

66654751 is a deficient number, since it is larger than the sum of its proper divisors (34521).

66654751 is a wasteful number, since it uses less digits than its factorization.

66654751 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34520.

The product of its digits is 151200, while the sum is 40.

The square root of 66654751 is about 8164.2360940874. The cubic root of 66654751 is about 405.4559737683.

The spelling of 66654751 in words is "sixty-six million, six hundred fifty-four thousand, seven hundred fifty-one".