66618344 has 32 divisors (see below), whose sum is σ = 136736040. Its totient is φ = 30240000.

The previous prime is 66618337. The next prime is 66618353. The reversal of 66618344 is 44381666.

It can be written as a sum of positive squares in 4 ways, for example, as 19695844 + 46922500 = 4438^2 + 6850^2 .

It is a junction number, because it is equal to n+sod(n) for n = 66618298 and 66618307.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1094 + ... + 11594.

Almost surely, 2^66618344 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66618344, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (68368020).

66618344 is an abundant number, since it is smaller than the sum of its proper divisors (70117696).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

66618344 is a wasteful number, since it uses less digits than its factorization.

66618344 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10581 (or 10577 counting only the distinct ones).

The product of its digits is 82944, while the sum is 38.

The square root of 66618344 is about 8162.0061259472. The cubic root of 66618344 is about 405.3821399514.

The spelling of 66618344 in words is "sixty-six million, six hundred eighteen thousand, three hundred forty-four".