66309688 has 16 divisors (see below), whose sum is σ = 125077680. Its totient is φ = 32955648.

The previous prime is 66309679. The next prime is 66309697. The reversal of 66309688 is 88690366.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (66309679) and next prime (66309697).

It is a zygodrome in base 2.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 23481 + ... + 26152.

It is an arithmetic number, because the mean of its divisors is an integer number (7817355).

Almost surely, 2^66309688 is an apocalyptic number.

It is an amenable number.

66309688 is a deficient number, since it is larger than the sum of its proper divisors (58767992).

66309688 is a wasteful number, since it uses less digits than its factorization.

66309688 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 49806 (or 49802 counting only the distinct ones).

The product of its (nonzero) digits is 373248, while the sum is 46.

The square root of 66309688 is about 8143.0760772573. The cubic root of 66309688 is about 404.7550985988.

The spelling of 66309688 in words is "sixty-six million, three hundred nine thousand, six hundred eighty-eight".