21312101212 has 24 divisors (see below), whose sum is σ = 38010301056. Its totient is φ = 10453949808.

The previous prime is 21312101141. The next prime is 21312101219. The reversal of 21312101212 is 21210121312.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21312101219) 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, 197638 + ... + 285805.

It is an arithmetic number, because the mean of its divisors is an integer number (1583762544).

Almost surely, 2^21312101212 is an apocalyptic number.

It is an amenable number.

21312101212 is a deficient number, since it is larger than the sum of its proper divisors (16698199844).

21312101212 is a wasteful number, since it uses less digits than its factorization.

21312101212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 483657 (or 483655 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 16.

Adding to 21312101212 its reverse (21210121312), we get a palindrome (42522222524).

The spelling of 21312101212 in words is "twenty-one billion, three hundred twelve million, one hundred one thousand, two hundred twelve".