66664272 has 80 divisors (see below), whose sum is σ = 180613440. Its totient is φ = 21159936.

The previous prime is 66664271. The next prime is 66664307. The reversal of 66664272 is 27246666.

It is a super-2 number, since 2×66664272² = 8888250322579968, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 66664272.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66664271) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 115248 + ... + 115824.

It is an arithmetic number, because the mean of its divisors is an integer number (2257668).

Almost surely, 2^66664272 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 66664272, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (90306720).

66664272 is an abundant number, since it is smaller than the sum of its proper divisors (113949168).

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

66664272 is a wasteful number, since it uses less digits than its factorization.

66664272 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 700 (or 694 counting only the distinct ones).

The product of its digits is 145152, while the sum is 39.

The square root of 66664272 is about 8164.8191651744. The cubic root of 66664272 is about 405.4752780313.

The spelling of 66664272 in words is "sixty-six million, six hundred sixty-four thousand, two hundred seventy-two".