21162000 has 80 divisors (see below), whose sum is σ = 68245632. Its totient is φ = 5641600.

The previous prime is 21161983. The next prime is 21162007. The reversal of 21162000 is 26112.

It is a tau number, because it is divible by the number of its divisors (80).

It is a Harshad number since it is a multiple of its sum of digits (12).

It is not an unprimeable number, because it can be changed into a prime (21162007) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4237 + ... + 7763.

Almost surely, 2^21162000 is an apocalyptic number.

21162000 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21162000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34122816).

21162000 is an abundant number, since it is smaller than the sum of its proper divisors (47083632).

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

21162000 is a wasteful number, since it uses less digits than its factorization.

21162000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3553 (or 3537 counting only the distinct ones).

The product of its (nonzero) digits is 24, while the sum is 12.

The square root of 21162000 is about 4600.2173861677. The cubic root of 21162000 is about 276.6000387935.

Adding to 21162000 its reverse (26112), we get a palindrome (21188112).

The spelling of 21162000 in words is "twenty-one million, one hundred sixty-two thousand".