133878144 has 64 divisors (see below), whose sum is σ = 356869440. Its totient is φ = 44468736.

The previous prime is 133878113. The next prime is 133878149. The reversal of 133878144 is 441878331.

It is a tau number, because it is divible by the number of its divisors (64).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (133878149) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 169719 + ... + 170505.

It is an arithmetic number, because the mean of its divisors is an integer number (5576085).

Almost surely, 2^133878144 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 133878144, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (178434720).

133878144 is an abundant number, since it is smaller than the sum of its proper divisors (222991296).

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

133878144 is an equidigital number, since it uses as much as digits as its factorization.

133878144 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1247 (or 1235 counting only the distinct ones).

The product of its digits is 64512, while the sum is 39.

The square root of 133878144 is about 11570.5723281089. The cubic root of 133878144 is about 511.5678319336.

The spelling of 133878144 in words is "one hundred thirty-three million, eight hundred seventy-eight thousand, one hundred forty-four".