66239716 has 6 divisors (see below), whose sum is σ = 115919510. Its totient is φ = 33119856.

The previous prime is 66239699. The next prime is 66239749. The reversal of 66239716 is 61793266.

It can be written as a sum of positive squares in only one way, i.e., 60217600 + 6022116 = 7760^2 + 2454^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8279961 + ... + 8279968.

Almost surely, 2^66239716 is an apocalyptic number.

It is an amenable number.

66239716 is a deficient number, since it is larger than the sum of its proper divisors (49679794).

66239716 is a wasteful number, since it uses less digits than its factorization.

66239716 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16559933 (or 16559931 counting only the distinct ones).

The product of its digits is 81648, while the sum is 40.

The square root of 66239716 is about 8138.7785324335. The cubic root of 66239716 is about 404.6126785273.

The spelling of 66239716 in words is "sixty-six million, two hundred thirty-nine thousand, seven hundred sixteen".