66697610090 has 8 divisors (see below), whose sum is σ = 120055698180. Its totient is φ = 26679044032.

The previous prime is 66697610087. The next prime is 66697610099. The reversal of 66697610090 is 9001679666.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 61235956681 + 5461653409 = 247459^2 + 73903^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (66697610099) 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, 3334880495 + ... + 3334880514.

Almost surely, 2^66697610090 is an apocalyptic number.

66697610090 is a deficient number, since it is larger than the sum of its proper divisors (53358088090).

66697610090 is a wasteful number, since it uses less digits than its factorization.

66697610090 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6669761016.

The product of its (nonzero) digits is 734832, while the sum is 50.

The spelling of 66697610090 in words is "sixty-six billion, six hundred ninety-seven million, six hundred ten thousand, ninety".