211221221210 has 16 divisors (see below), whose sum is σ = 380213358696. Its totient is φ = 84485119488.

The previous prime is 211221221207. The next prime is 211221221249. The reversal of 211221221210 is 12122122112.

It can be written as a sum of positive squares in 4 ways, for example, as 96020036641 + 115201184569 = 309871^2 + 339413^2 .

It is a super-2 number, since 2×211221221210² (a number of 23 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 149459 + ... + 666918.

Almost surely, 2^211221221210 is an apocalyptic number.

211221221210 is a deficient number, since it is larger than the sum of its proper divisors (168992137486).

211221221210 is a wasteful number, since it uses less digits than its factorization.

211221221210 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 842257.

The product of its (nonzero) digits is 64, while the sum is 17.

Adding to 211221221210 its reverse (12122122112), we get a palindrome (223343343322).

The spelling of 211221221210 in words is "two hundred eleven billion, two hundred twenty-one million, two hundred twenty-one thousand, two hundred ten".