1221110012001 has 24 divisors (see below), whose sum is σ = 1792717669792. Its totient is φ = 738783936000.

The previous prime is 1221110011993. The next prime is 1221110012009. The reversal of 1221110012001 is 1002100111221.

It is an interprime number because it is at equal distance from previous prime (1221110011993) and next prime (1221110012009).

It is not a de Polignac number, because 1221110012001 - 2³ = 1221110011993 is a prime.

It is a super-2 number, since 2×1221110012001² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1221110012009) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2705575 + ... + 3124476.

Almost surely, 2^{1221110012001} is an apocalyptic number.

1221110012001 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1221110012001 is a deficient number, since it is larger than the sum of its proper divisors (571607657791).

1221110012001 is a wasteful number, since it uses less digits than its factorization.

1221110012001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5830653 (or 5830642 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 12.

Adding to 1221110012001 its reverse (1002100111221), we get a palindrome (2223210123222).

The spelling of 1221110012001 in words is "one trillion, two hundred twenty-one billion, one hundred ten million, twelve thousand, one".