21830070 has 64 divisors (see below), whose sum is σ = 54282240. Its totient is φ = 5616000.

The previous prime is 21830063. The next prime is 21830071. The reversal of 21830070 is 7003812.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21830071) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 144495 + ... + 144645.

It is an arithmetic number, because the mean of its divisors is an integer number (848160).

Almost surely, 2^21830070 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21830070, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27141120).

21830070 is an abundant number, since it is smaller than the sum of its proper divisors (32452170).

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

21830070 is a wasteful number, since it uses less digits than its factorization.

21830070 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 301.

The product of its (nonzero) digits is 336, while the sum is 21.

The square root of 21830070 is about 4672.2660455073. The cubic root of 21830070 is about 279.4806273462.

Adding to 21830070 its reverse (7003812), we get a palindrome (28833882).

The spelling of 21830070 in words is "twenty-one million, eight hundred thirty thousand, seventy".