221020121212010 has 16 divisors (see below), whose sum is σ = 398353560481800. Its totient is φ = 88293083529216.

The previous prime is 221020121211979. The next prime is 221020121212039. The reversal of 221020121212010 is 10212121020122.

It can be written as a sum of positive squares in 4 ways, for example, as 161054348736961 + 59965772475049 = 12690719^2 + 7743757^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 221020121212010.

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, 14370611375 + ... + 14370626754.

Almost surely, 2^{221020121212010} is an apocalyptic number.

221020121212010 is a deficient number, since it is larger than the sum of its proper divisors (177333439269790).

221020121212010 is a wasteful number, since it uses less digits than its factorization.

221020121212010 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28741238905.

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

Adding to 221020121212010 its reverse (10212121020122), we get a palindrome (231232242232132).

The spelling of 221020121212010 in words is "two hundred twenty-one trillion, twenty billion, one hundred twenty-one million, two hundred twelve thousand, ten".