66870144 has 128 divisors (see below), whose sum is σ = 215424000. Its totient is φ = 20252160.

The previous prime is 66870127. The next prime is 66870149. The reversal of 66870144 is 44107866.

It is a tau number, because it is divible by the number of its divisors (128).

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

It is a junction number, because it is equal to n+sod(n) for n = 66870099 and 66870108.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66870149) 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, 37137 + ... + 38895.

It is an arithmetic number, because the mean of its divisors is an integer number (1683000).

Almost surely, 2^66870144 is an apocalyptic number.

66870144 is a gapful number since it is divisible by the number (64) 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 66870144, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (107712000).

66870144 is an abundant number, since it is smaller than the sum of its proper divisors (148553856).

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

66870144 is a wasteful number, since it uses less digits than its factorization.

66870144 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1793 (or 1775 counting only the distinct ones).

The product of its (nonzero) digits is 32256, while the sum is 36.

The square root of 66870144 is about 8177.4167070047. The cubic root of 66870144 is about 405.8922441268.

The spelling of 66870144 in words is "sixty-six million, eight hundred seventy thousand, one hundred forty-four".