21000321210 has 64 divisors (see below), whose sum is σ = 55803354624. Its totient is φ = 5014996800.

The previous prime is 21000321193. The next prime is 21000321217. The reversal of 21000321210 is 1212300012.

It is not an unprimeable number, because it can be changed into a prime (21000321217) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 452796 + ... + 497015.

It is an arithmetic number, because the mean of its divisors is an integer number (871927416).

Almost surely, 2^21000321210 is an apocalyptic number.

21000321210 is an abundant number, since it is smaller than the sum of its proper divisors (34803033414).

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

21000321210 is a wasteful number, since it uses less digits than its factorization.

21000321210 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 949899.

The product of its (nonzero) digits is 24, while the sum is 12.

Adding to 21000321210 its reverse (1212300012), we get a palindrome (22212621222).

The spelling of 21000321210 in words is "twenty-one billion, three hundred twenty-one thousand, two hundred ten".