21110628 has 144 divisors (see below), whose sum is σ = 64827392. Its totient is φ = 5227200.

The previous prime is 21110611. The next prime is 21110647. The reversal of 21110628 is 82601112.

It is a super-2 number, since 2×21110628² = 891317229108768, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 315051 + ... + 315117.

Almost surely, 2^21110628 is an apocalyptic number.

21110628 is a gapful number since it is divisible by the number (28) 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 21110628, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32413696).

21110628 is an abundant number, since it is smaller than the sum of its proper divisors (43716764).

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

21110628 is a wasteful number, since it uses less digits than its factorization.

21110628 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 134 (or 121 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 21.

The square root of 21110628 is about 4594.6303442170. The cubic root of 21110628 is about 276.3760364804.

The spelling of 21110628 in words is "twenty-one million, one hundred ten thousand, six hundred twenty-eight".