21024700 has 18 divisors (see below), whose sum is σ = 45623816. Its totient is φ = 8409840.

The previous prime is 21024643. The next prime is 21024743. The reversal of 21024700 is 742012.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 105024 + ... + 105223.

Almost surely, 2^21024700 is an apocalyptic number.

21024700 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21024700 is an abundant number, since it is smaller than the sum of its proper divisors (24599116).

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

21024700 is a wasteful number, since it uses less digits than its factorization.

21024700 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 210261 (or 210254 counting only the distinct ones).

The product of its (nonzero) digits is 112, while the sum is 16.

The square root of 21024700 is about 4585.2698939103. The cubic root of 21024700 is about 276.0005426020. Note that the first 3 decimals are identical.

Adding to 21024700 its reverse (742012), we get a palindrome (21766712).

The spelling of 21024700 in words is "twenty-one million, twenty-four thousand, seven hundred".