21030321210 has 32 divisors (see below), whose sum is σ = 52213213440. Its totient is φ = 5414703168.

The previous prime is 21030321199. The next prime is 21030321227. The reversal of 21030321210 is 1212303012.

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

It is an alternating number because its digits alternate between even and odd.

It is a self number, because there is not a number n which added to its sum of digits gives 21030321210.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 12085522 + ... + 12087261.

It is an arithmetic number, because the mean of its divisors is an integer number (1631662920).

Almost surely, 2^21030321210 is an apocalyptic number.

21030321210 is an abundant number, since it is smaller than the sum of its proper divisors (31182892230).

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

21030321210 is a wasteful number, since it uses less digits than its factorization.

21030321210 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24172822.

The product of its (nonzero) digits is 72, while the sum is 15.

Adding to 21030321210 its reverse (1212303012), we get a palindrome (22242624222).

The spelling of 21030321210 in words is "twenty-one billion, thirty million, three hundred twenty-one thousand, two hundred ten".