66644116642 has 8 divisors (see below), whose sum is σ = 100234181916. Its totient is φ = 33232722672.

The previous prime is 66644116613. The next prime is 66644116657. The reversal of 66644116642 is 24661144666.

It can be written as a sum of positive squares in 2 ways, for example, as 64633401361 + 2010715281 = 254231^2 + 44841^2 .

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

It is a junction number, because it is equal to n+sod(n) for n = 66644116592 and 66644116601.

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, 44666893 + ... + 44668384.

Almost surely, 2^66644116642 is an apocalyptic number.

66644116642 is a deficient number, since it is larger than the sum of its proper divisors (33590065274).

66644116642 is a wasteful number, since it uses less digits than its factorization.

66644116642 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 89335652.

The product of its digits is 995328, while the sum is 46.

The spelling of 66644116642 in words is "sixty-six billion, six hundred forty-four million, one hundred sixteen thousand, six hundred forty-two".