66749599 has 16 divisors (see below), whose sum is σ = 82748736. Its totient is φ = 52531200.

The previous prime is 66749581. The next prime is 66749647. The reversal of 66749599 is 99594766.

It is a cyclic number.

It is not a de Polignac number, because 66749599 - 2⁷ = 66749471 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66749509) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1962 + ... + 11719.

It is an arithmetic number, because the mean of its divisors is an integer number (5171796).

Almost surely, 2^66749599 is an apocalyptic number.

66749599 is a deficient number, since it is larger than the sum of its proper divisors (15999137).

66749599 is a wasteful number, since it uses less digits than its factorization.

66749599 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13746.

The product of its digits is 3674160, while the sum is 55.

The square root of 66749599 is about 8170.0427783458. The cubic root of 66749599 is about 405.6482004341.

The spelling of 66749599 in words is "sixty-six million, seven hundred forty-nine thousand, five hundred ninety-nine".