40389128 has 32 divisors (see below), whose sum is σ = 82555200. Its totient is φ = 18412608.

The previous prime is 40389119. The next prime is 40389133. The reversal of 40389128 is 82198304.

It is a happy number.

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, 6293 + ... + 10971.

It is an arithmetic number, because the mean of its divisors is an integer number (2579850).

Almost surely, 2^40389128 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 40389128, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (41277600).

40389128 is an abundant number, since it is smaller than the sum of its proper divisors (42166072).

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

40389128 is a wasteful number, since it uses less digits than its factorization.

40389128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4781 (or 4777 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 35.

The square root of 40389128 is about 6355.2441337843. The cubic root of 40389128 is about 343.1006116576.

The spelling of 40389128 in words is "forty million, three hundred eighty-nine thousand, one hundred twenty-eight".