21160000 has 105 divisors (see below), whose sum is σ = 54850411. Its totient is φ = 8096000.

The previous prime is 21159973. The next prime is 21160001. The reversal of 21160000 is 6112.

The square root of 21160000 is 4600.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 2 ways, for example, as 1658944 + 19501056 = 1288^2 + 4416^2 .

It is a Harshad number since it is a multiple of its sum of digits (10).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21160001) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 14 ways as a sum of consecutive naturals, for example, 919989 + ... + 920011.

Almost surely, 2^21160000 is an apocalyptic number.

21160000 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

21160000 is the 4600-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21160000

21160000 is an abundant number, since it is smaller than the sum of its proper divisors (33690411).

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

21160000 is an frugal number, since it uses more digits than its factorization.

21160000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 78 (or 30 counting only the distinct ones).

The product of its (nonzero) digits is 12, while the sum is 10.

The cubic root of 21160000 is about 276.5913247856.

Adding to 21160000 its reverse (6112), we get a palindrome (21166112).

The spelling of 21160000 in words is "twenty-one million, one hundred sixty thousand".