21530050200 has 144 divisors (see below), whose sum is σ = 72553637520. Its totient is φ = 5721611520.

The previous prime is 21530050189. The next prime is 21530050237. The reversal of 21530050200 is 205003512.

It is a happy number.

It is a super-2 number, since 2×21530050200² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 506989 + ... + 547811.

It is an arithmetic number, because the mean of its divisors is an integer number (503844705).

Almost surely, 2^21530050200 is an apocalyptic number.

21530050200 is a gapful number since it is divisible by the number (20) 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 21530050200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36276818760).

21530050200 is an abundant number, since it is smaller than the sum of its proper divisors (51023587320).

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

21530050200 is a wasteful number, since it uses less digits than its factorization.

21530050200 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41138 (or 41126 counting only the distinct ones).

The product of its (nonzero) digits is 300, while the sum is 18.

Adding to 21530050200 its reverse (205003512), we get a palindrome (21735053712).

The spelling of 21530050200 in words is "twenty-one billion, five hundred thirty million, fifty thousand, two hundred".