66938880 has 96 divisors (see below), whose sum is σ = 214250400. Its totient is φ = 17842176.

The previous prime is 66938869. The next prime is 66938903. The reversal of 66938880 is 8883966.

It is a tau number, because it is divible by the number of its divisors (96).

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a zygodrome in base 4.

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, 29631 + ... + 31809.

It is an arithmetic number, because the mean of its divisors is an integer number (2231775).

Almost surely, 2^66938880 is an apocalyptic number.

66938880 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 66938880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (107125200).

66938880 is an abundant number, since it is smaller than the sum of its proper divisors (147311520).

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

66938880 is a wasteful number, since it uses less digits than its factorization.

66938880 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2209 (or 2189 counting only the distinct ones).

The product of its (nonzero) digits is 497664, while the sum is 48.

The square root of 66938880 is about 8181.6184218038. The cubic root of 66938880 is about 406.0312690777.

The spelling of 66938880 in words is "sixty-six million, nine hundred thirty-eight thousand, eight hundred eighty".