1221010110001 has 32 divisors (see below), whose sum is σ = 1397264256000. Its totient is φ = 1056149455680.

The previous prime is 1221010109947. The next prime is 1221010110037. The reversal of 1221010110001 is 1000110101221.

It is not a de Polignac number, because 1221010110001 - 2¹⁵ = 1221010077233 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1221010110001.

It is not an unprimeable number, because it can be changed into a prime (1221010110101) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 70574050 + ... + 70591348.

It is an arithmetic number, because the mean of its divisors is an integer number (43664508000).

Almost surely, 2^{1221010110001} is an apocalyptic number.

1221010110001 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1221010110001 is a deficient number, since it is larger than the sum of its proper divisors (176254145999).

1221010110001 is a wasteful number, since it uses less digits than its factorization.

1221010110001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18789.

The product of its (nonzero) digits is 4, while the sum is 10.

Adding to 1221010110001 its reverse (1000110101221), we get a palindrome (2221120211222).

The spelling of 1221010110001 in words is "one trillion, two hundred twenty-one billion, ten million, one hundred ten thousand, one".