66943620 has 144 divisors (see below), whose sum is σ = 217945728. Its totient is φ = 16573440.

The previous prime is 66943607. The next prime is 66943621. The reversal of 66943620 is 2634966.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (66943621) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 400777 + ... + 400943.

It is an arithmetic number, because the mean of its divisors is an integer number (1513512).

Almost surely, 2^66943620 is an apocalyptic number.

66943620 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66943620, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (108972864).

66943620 is an abundant number, since it is smaller than the sum of its proper divisors (151002108).

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

66943620 is a wasteful number, since it uses less digits than its factorization.

66943620 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 330 (or 325 counting only the distinct ones).

The product of its (nonzero) digits is 46656, while the sum is 36.

The square root of 66943620 is about 8181.9080904151. The cubic root of 66943620 is about 406.0408526599.

The spelling of 66943620 in words is "sixty-six million, nine hundred forty-three thousand, six hundred twenty".