21115050 has 96 divisors (see below), whose sum is σ = 58281984. Its totient is φ = 5016000.

The previous prime is 21115027. The next prime is 21115063. The reversal of 21115050 is 5051112.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 110455 + ... + 110645.

It is an arithmetic number, because the mean of its divisors is an integer number (607104).

Almost surely, 2^21115050 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21115050, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29140992).

21115050 is an abundant number, since it is smaller than the sum of its proper divisors (37166934).

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

21115050 is a wasteful number, since it uses less digits than its factorization.

21115050 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 284 (or 279 counting only the distinct ones).

The product of its (nonzero) digits is 50, while the sum is 15.

The square root of 21115050 is about 4595.1115329228. Note that the first 3 decimals coincide. The cubic root of 21115050 is about 276.3953324405.

Adding to 21115050 its reverse (5051112), we get a palindrome (26166162).

The spelling of 21115050 in words is "twenty-one million, one hundred fifteen thousand, fifty".