66644622 has 72 divisors (see below), whose sum is σ = 163203768. Its totient is φ = 19625760.

The previous prime is 66644597. The next prime is 66644623. The reversal of 66644622 is 22644666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66644623) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 80173 + ... + 80999.

It is an arithmetic number, because the mean of its divisors is an integer number (2266719).

Almost surely, 2^66644622 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66644622, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (81601884).

66644622 is an abundant number, since it is smaller than the sum of its proper divisors (96559146).

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

66644622 is a wasteful number, since it uses less digits than its factorization.

66644622 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 894 (or 880 counting only the distinct ones).

The product of its digits is 82944, while the sum is 36.

The square root of 66644622 is about 8163.6157430394. The cubic root of 66644622 is about 405.4354347392.

The spelling of 66644622 in words is "sixty-six million, six hundred forty-four thousand, six hundred twenty-two".