21002101312 has 14 divisors (see below), whose sum is σ = 41676044918. Its totient is φ = 10501050624.

The previous prime is 21002101303. The next prime is 21002101319. The reversal of 21002101312 is 21310120012.

It can be written as a sum of positive squares in only one way, i.e., 20430700096 + 571401216 = 142936^2 + 23904^2 .

It is a junction number, because it is equal to n+sod(n) for n = 21002101292 and 21002101301.

It is not an unprimeable number, because it can be changed into a prime (21002101319) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 164078853 + ... + 164078980.

Almost surely, 2^21002101312 is an apocalyptic number.

It is an amenable number.

21002101312 is a deficient number, since it is larger than the sum of its proper divisors (20673943606).

21002101312 is an equidigital number, since it uses as much as digits as its factorization.

21002101312 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 328157845 (or 328157835 counting only the distinct ones).

The product of its (nonzero) digits is 24, while the sum is 13.

Adding to 21002101312 its reverse (21310120012), we get a palindrome (42312221324).

The spelling of 21002101312 in words is "twenty-one billion, two million, one hundred one thousand, three hundred twelve".