21207980212 has 6 divisors (see below), whose sum is σ = 37113965378. Its totient is φ = 10603990104.

The previous prime is 21207980207. The next prime is 21207980243. The reversal of 21207980212 is 21208970212.

It can be written as a sum of positive squares in only one way, i.e., 16173226276 + 5034753936 = 127174^2 + 70956^2 .

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2650997523 + ... + 2650997530.

Almost surely, 2^21207980212 is an apocalyptic number.

It is an amenable number.

21207980212 is a deficient number, since it is larger than the sum of its proper divisors (15905985166).

21207980212 is a wasteful number, since it uses less digits than its factorization.

21207980212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5301995057 (or 5301995055 counting only the distinct ones).

The product of its (nonzero) digits is 8064, while the sum is 34.

The spelling of 21207980212 in words is "twenty-one billion, two hundred seven million, nine hundred eighty thousand, two hundred twelve".