66749770 has 16 divisors (see below), whose sum is σ = 120652488. Its totient is φ = 26588160.

The previous prime is 66749759. The next prime is 66749783. The reversal of 66749770 is 7794766.

It can be written as a sum of positive squares in 4 ways, for example, as 41075281 + 25674489 = 6409^2 + 5067^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 66749770.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11439 + ... + 16258.

Almost surely, 2^66749770 is an apocalyptic number.

66749770 is a deficient number, since it is larger than the sum of its proper divisors (53902718).

66749770 is a wasteful number, since it uses less digits than its factorization.

66749770 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27945.

The product of its (nonzero) digits is 444528, while the sum is 46.

The square root of 66749770 is about 8170.0532434006. The cubic root of 66749770 is about 405.6485468321.

The spelling of 66749770 in words is "sixty-six million, seven hundred forty-nine thousand, seven hundred seventy".