21221221212010 has 32 divisors (see below), whose sum is σ = 39515674631760. Its totient is φ = 8195720343552.

The previous prime is 21221221212007. The next prime is 21221221212053. The reversal of 21221221212010 is 1021212212212.

It can be written as a sum of positive squares in 8 ways, for example, as 20819408483241 + 401812728769 = 4562829^2 + 633887^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 64993482 + ... + 65319178.

Almost surely, 2^{21221221212010} is an apocalyptic number.

21221221212010 is a deficient number, since it is larger than the sum of its proper divisors (18294453419750).

21221221212010 is a wasteful number, since it uses less digits than its factorization.

21221221212010 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 550410.

The product of its (nonzero) digits is 128, while the sum is 19.

Adding to 21221221212010 its reverse (1021212212212), we get a palindrome (22242433424222).

The spelling of 21221221212010 in words is "twenty-one trillion, two hundred twenty-one billion, two hundred twenty-one million, two hundred twelve thousand, ten".