66888378 has 48 divisors (see below), whose sum is σ = 151164000. Its totient is φ = 21355488.

The previous prime is 66888377. The next prime is 66888407. The reversal of 66888378 is 87388866.

It is a happy number.

It is a super-2 number, since 2×66888378² = 8948110222941768, which contains 22 as substring.

It is a Smith number, since the sum of its digits (54) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (66888377) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 43873 + ... + 45371.

It is an arithmetic number, because the mean of its divisors is an integer number (3149250).

Almost surely, 2^66888378 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66888378, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (75582000).

66888378 is an abundant number, since it is smaller than the sum of its proper divisors (84275622).

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

66888378 is a wasteful number, since it uses less digits than its factorization.

66888378 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1611 (or 1608 counting only the distinct ones).

The product of its digits is 3096576, while the sum is 54.

The square root of 66888378 is about 8178.5315307823. The cubic root of 66888378 is about 405.9291333678.

The spelling of 66888378 in words is "sixty-six million, eight hundred eighty-eight thousand, three hundred seventy-eight".