21830120 has 32 divisors (see below), whose sum is σ = 52897320. Its totient is φ = 8060160.

The previous prime is 21830119. The next prime is 21830143. The reversal of 21830120 is 2103812.

It can be written as a sum of positive squares in 4 ways, for example, as 6791236 + 15038884 = 2606^2 + 3878^2 .

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, 20471 + ... + 21510.

Almost surely, 2^21830120 is an apocalyptic number.

21830120 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21830120 is an abundant number, since it is smaller than the sum of its proper divisors (31067200).

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

21830120 is a wasteful number, since it uses less digits than its factorization.

21830120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42005 (or 42001 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 17.

The square root of 21830120 is about 4672.2713962269. The cubic root of 21830120 is about 279.4808407219.

Adding to 21830120 its reverse (2103812), we get a palindrome (23933932).

The spelling of 21830120 in words is "twenty-one million, eight hundred thirty thousand, one hundred twenty".