21211030320 has 40 divisors (see below), whose sum is σ = 65754194736. Its totient is φ = 5656274688.

The previous prime is 21211030303. The next prime is 21211030327. The reversal of 21211030320 is 2303011212.

It is a tau number, because it is divible by the number of its divisors (40).

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

It is a self number, because there is not a number n which added to its sum of digits gives 21211030320.

It is not an unprimeable number, because it can be changed into a prime (21211030327) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 44189407 + ... + 44189886.

Almost surely, 2^21211030320 is an apocalyptic number.

21211030320 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21211030320 is an abundant number, since it is smaller than the sum of its proper divisors (44543164416).

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

21211030320 is a wasteful number, since it uses less digits than its factorization.

21211030320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 88379309 (or 88379303 counting only the distinct ones).

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

Adding to 21211030320 its reverse (2303011212), we get a palindrome (23514041532).

The spelling of 21211030320 in words is "twenty-one billion, two hundred eleven million, thirty thousand, three hundred twenty".