66451774 has 4 divisors (see below), whose sum is σ = 99677664. Its totient is φ = 33225886.

The previous prime is 66451733. The next prime is 66451823. The reversal of 66451774 is 47715466.

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

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 16612942 + ... + 16612945.

It is an arithmetic number, because the mean of its divisors is an integer number (24919416).

Almost surely, 2^66451774 is an apocalyptic number.

66451774 is a deficient number, since it is larger than the sum of its proper divisors (33225890).

66451774 is a wasteful number, since it uses less digits than its factorization.

66451774 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33225889.

The product of its digits is 141120, while the sum is 40.

The square root of 66451774 is about 8151.7957530841. The cubic root of 66451774 is about 405.0439905475.

The spelling of 66451774 in words is "sixty-six million, four hundred fifty-one thousand, seven hundred seventy-four".