21124950 has 192 divisors, whose sum is σ = 68567040. Its totient is φ = 4176000.

The previous prime is 21124927. The next prime is 21124967. The reversal of 21124950 is 5942112.

It is a self number, because there is not a number n which added to its sum of digits gives 21124950.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 358021 + ... + 358079.

It is an arithmetic number, because the mean of its divisors is an integer number (357120).

Almost surely, 2^21124950 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21124950, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34283520).

21124950 is an abundant number, since it is smaller than the sum of its proper divisors (47442090).

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

21124950 is a wasteful number, since it uses less digits than its factorization.

21124950 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 123 (or 118 counting only the distinct ones).

The product of its (nonzero) digits is 720, while the sum is 24.

The square root of 21124950 is about 4596.1886384264. The cubic root of 21124950 is about 276.4385225861.

The spelling of 21124950 in words is "twenty-one million, one hundred twenty-four thousand, nine hundred fifty".