19812021212 has 12 divisors (see below), whose sum is σ = 34690895400. Its totient is φ = 9900336816.

The previous prime is 19812021191. The next prime is 19812021217. The reversal of 19812021212 is 21212021891.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19812021217) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1410587 + ... + 1424562.

It is an arithmetic number, because the mean of its divisors is an integer number (2890907950).

Almost surely, 2^19812021212 is an apocalyptic number.

It is an amenable number.

19812021212 is a deficient number, since it is larger than the sum of its proper divisors (14878874188).

19812021212 is a wasteful number, since it uses less digits than its factorization.

19812021212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2836900 (or 2836898 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 29.

The spelling of 19812021212 in words is "nineteen billion, eight hundred twelve million, twenty-one thousand, two hundred twelve".