66728760 has 256 divisors, whose sum is σ = 249523200. Its totient is φ = 13934592.

The previous prime is 66728737. The next prime is 66728807. The reversal of 66728760 is 6782766.

It is a super-2 number, since 2×66728760² = 8905454822275200, which contains 22 as substring.

It is a hoax number, since the sum of its digits (42) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 590464 + ... + 590576.

It is an arithmetic number, because the mean of its divisors is an integer number (974700).

Almost surely, 2^66728760 is an apocalyptic number.

66728760 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 66728760, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (124761600).

66728760 is an abundant number, since it is smaller than the sum of its proper divisors (182794440).

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

66728760 is a wasteful number, since it uses less digits than its factorization.

66728760 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 190 (or 186 counting only the distinct ones).

The product of its (nonzero) digits is 169344, while the sum is 42.

The square root of 66728760 is about 8168.7673488722. The cubic root of 66728760 is about 405.6059820397.

The spelling of 66728760 in words is "sixty-six million, seven hundred twenty-eight thousand, seven hundred sixty".