21012112210 has 16 divisors (see below), whose sum is σ = 37859304600. Its totient is φ = 8396510976.

The previous prime is 21012112171. The next prime is 21012112241. The reversal of 21012112210 is 1221121012.

It can be written as a sum of positive squares in 4 ways, for example, as 16558285041 + 4453827169 = 128679^2 + 66737^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1031145 + ... + 1051324.

Almost surely, 2^21012112210 is an apocalyptic number.

21012112210 is a deficient number, since it is larger than the sum of its proper divisors (16847192390).

21012112210 is a wasteful number, since it uses less digits than its factorization.

21012112210 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2083485.

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 21012112210 its reverse (1221121012), we get a palindrome (22233233222).

The spelling of 21012112210 in words is "twenty-one billion, twelve million, one hundred twelve thousand, two hundred ten".