21106000 has 80 divisors (see below), whose sum is σ = 52170768. Its totient is φ = 8256000.

The previous prime is 21105977. The next prime is 21106037. The reversal of 21106000 is 60112.

It can be written as a sum of positive squares in 8 ways, for example, as 8088336 + 13017664 = 2844^2 + 3608^2 .

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 (10).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 121914 + ... + 122086.

Almost surely, 2^21106000 is an apocalyptic number.

21106000 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 21106000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26085384).

21106000 is an abundant number, since it is smaller than the sum of its proper divisors (31064768).

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

21106000 is a wasteful number, since it uses less digits than its factorization.

21106000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 257 (or 241 counting only the distinct ones).

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

The square root of 21106000 is about 4594.1266852363. The cubic root of 21106000 is about 276.3558387269.

Adding to 21106000 its reverse (60112), we get a palindrome (21166112).

The spelling of 21106000 in words is "twenty-one million, one hundred six thousand".