66749737 has 4 divisors (see below), whose sum is σ = 68009220. Its totient is φ = 65490256.

The previous prime is 66749713. The next prime is 66749741. The reversal of 66749737 is 73794766.

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

It can be written as a sum of positive squares in 2 ways, for example, as 16353936 + 50395801 = 4044^2 + 7099^2 .

It is a cyclic number.

It is not a de Polignac number, because 66749737 - 2²³ = 58361129 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66743737) 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, 629662 + ... + 629767.

It is an arithmetic number, because the mean of its divisors is an integer number (17002305).

Almost surely, 2^66749737 is an apocalyptic number.

It is an amenable number.

66749737 is a deficient number, since it is larger than the sum of its proper divisors (1259483).

66749737 is a wasteful number, since it uses less digits than its factorization.

66749737 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1259482.

The product of its digits is 1333584, while the sum is 49.

The square root of 66749737 is about 8170.0512238296. The cubic root of 66749737 is about 405.6484799834.

The spelling of 66749737 in words is "sixty-six million, seven hundred forty-nine thousand, seven hundred thirty-seven".