21211220312 has 32 divisors (see below), whose sum is σ = 40583274480. Its totient is φ = 10389624960.

The previous prime is 21211220311. The next prime is 21211220347. The reversal of 21211220312 is 21302211212.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21211220311) 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, 242423 + ... + 318105.

Almost surely, 2^21211220312 is an apocalyptic number.

It is an amenable number.

21211220312 is a deficient number, since it is larger than the sum of its proper divisors (19372054168).

21211220312 is a wasteful number, since it uses less digits than its factorization.

21211220312 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 76403 (or 76399 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 17.

Adding to 21211220312 its reverse (21302211212), we get a palindrome (42513431524).

The spelling of 21211220312 in words is "twenty-one billion, two hundred eleven million, two hundred twenty thousand, three hundred twelve".