21128034 has 16 divisors (see below), whose sum is σ = 42305472. Its totient is φ = 7034448.

The previous prime is 21128033. The next prime is 21128069. The reversal of 21128034 is 43082112.

It is a self number, because there is not a number n which added to its sum of digits gives 21128034.

It is not an unprimeable number, because it can be changed into a prime (21128033) 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, 5827 + ... + 8729.

It is an arithmetic number, because the mean of its divisors is an integer number (2644092).

Almost surely, 2^21128034 is an apocalyptic number.

21128034 is an abundant number, since it is smaller than the sum of its proper divisors (21177438).

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

21128034 is a wasteful number, since it uses less digits than its factorization.

21128034 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4121.

The product of its (nonzero) digits is 384, while the sum is 21.

The square root of 21128034 is about 4596.5241215510. The cubic root of 21128034 is about 276.4519742144.

The spelling of 21128034 in words is "twenty-one million, one hundred twenty-eight thousand, thirty-four".