21140128 has 24 divisors (see below), whose sum is σ = 43430688. Its totient is φ = 10110144.

The previous prime is 21140123. The next prime is 21140149. The reversal of 21140128 is 82104112.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (21140123) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13626 + ... + 15097.

It is an arithmetic number, because the mean of its divisors is an integer number (1809612).

Almost surely, 2^21140128 is an apocalyptic number.

It is an amenable number.

21140128 is an abundant number, since it is smaller than the sum of its proper divisors (22290560).

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

21140128 is a wasteful number, since it uses less digits than its factorization.

21140128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28756 (or 28748 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 19.

The square root of 21140128 is about 4597.8394926313. The cubic root of 21140128 is about 276.5047125562.

The spelling of 21140128 in words is "twenty-one million, one hundred forty thousand, one hundred twenty-eight".