21000500010 has 144 divisors (see below), whose sum is σ = 66288658176. Its totient is φ = 4517715456.

The previous prime is 21000499981. The next prime is 21000500041. The reversal of 21000500010 is 1000500012.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a junction number, because it is equal to n+sod(n) for n = 21000499965 and 21000500001.

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 124399 + ... + 239741.

It is an arithmetic number, because the mean of its divisors is an integer number (460337904).

Almost surely, 2^21000500010 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21000500010, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33144329088).

21000500010 is an abundant number, since it is smaller than the sum of its proper divisors (45288158166).

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

21000500010 is a wasteful number, since it uses less digits than its factorization.

21000500010 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 115397 (or 115377 counting only the distinct ones).

The product of its (nonzero) digits is 10, while the sum is 9.

The spelling of 21000500010 in words is "twenty-one billion, five hundred thousand, ten".