21528100 has 36 divisors (see below), whose sum is σ = 50965488. Its totient is φ = 7828000.

The previous prime is 21528077. The next prime is 21528113. The reversal of 21528100 is 182512.

It is a super-2 number, since 2×21528100² = 926918179220000, which contains 22 as substring.

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 11 ways as a sum of consecutive naturals, for example, 8686 + ... + 10885.

It is an arithmetic number, because the mean of its divisors is an integer number (1415708).

Almost surely, 2^21528100 is an apocalyptic number.

21528100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21528100 is an abundant number, since it is smaller than the sum of its proper divisors (29437388).

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

21528100 is a wasteful number, since it uses less digits than its factorization.

21528100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19596 (or 19589 counting only the distinct ones).

The product of its (nonzero) digits is 160, while the sum is 19.

The square root of 21528100 is about 4639.8383592535. The cubic root of 21528100 is about 278.1859770355.

The spelling of 21528100 in words is "twenty-one million, five hundred twenty-eight thousand, one hundred".