21323002100 has 36 divisors (see below), whose sum is σ = 46565668044. Its totient is φ = 8474868480.

The previous prime is 21323002069. The next prime is 21323002109. The reversal of 21323002100 is 120032312.

It is a happy number.

It can be written as a sum of positive squares in 6 ways, for example, as 195216784 + 21127785316 = 13972^2 + 145354^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21323002109) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 663377 + ... + 694776.

It is an arithmetic number, because the mean of its divisors is an integer number (1293490779).

Almost surely, 2^21323002100 is an apocalyptic number.

21323002100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21323002100 is an abundant number, since it is smaller than the sum of its proper divisors (25242665944).

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

21323002100 is a wasteful number, since it uses less digits than its factorization.

21323002100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1358324 (or 1358317 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 14.

Adding to 21323002100 its reverse (120032312), we get a palindrome (21443034412).

The spelling of 21323002100 in words is "twenty-one billion, three hundred twenty-three million, two thousand, one hundred".