66797690 has 16 divisors (see below), whose sum is σ = 121301928. Its totient is φ = 26482176.

The previous prime is 66797683. The next prime is 66797693. The reversal of 66797690 is 9679766.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 55190041 + 11607649 = 7429^2 + 3407^2 .

It is a super-2 number, since 2×66797690² = 8923862778672200, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (66797693) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 28427 + ... + 30686.

Almost surely, 2^66797690 is an apocalyptic number.

66797690 is a deficient number, since it is larger than the sum of its proper divisors (54504238).

66797690 is a wasteful number, since it uses less digits than its factorization.

66797690 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 59233.

The product of its (nonzero) digits is 857304, while the sum is 50.

The square root of 66797690 is about 8172.9853786728. The cubic root of 66797690 is about 405.7455959981.

The spelling of 66797690 in words is "sixty-six million, seven hundred ninety-seven thousand, six hundred ninety".