21011010321 has 96 divisors (see below), whose sum is σ = 34583915520. Its totient is φ = 11300155776.

The previous prime is 21011010289. The next prime is 21011010389. The reversal of 21011010321 is 12301011012.

It is not a de Polignac number, because 21011010321 - 2⁵ = 21011010289 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21011010297 and 21011010306.

It is not an unprimeable number, because it can be changed into a prime (21011010121) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 19765236 + ... + 19766298.

It is an arithmetic number, because the mean of its divisors is an integer number (360249120).

Almost surely, 2^21011010321 is an apocalyptic number.

21011010321 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

21011010321 is a deficient number, since it is larger than the sum of its proper divisors (13572905199).

21011010321 is a wasteful number, since it uses less digits than its factorization.

21011010321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1235 (or 1228 counting only the distinct ones).

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

Adding to 21011010321 its reverse (12301011012), we get a palindrome (33312021333).

The spelling of 21011010321 in words is "twenty-one billion, eleven million, ten thousand, three hundred twenty-one".