1221010101009 has 12 divisors (see below), whose sum is σ = 1776369613200. Its totient is φ = 808150569624.

The previous prime is 1221010100987. The next prime is 1221010101029. The reversal of 1221010101009 is 9001010101221.

It is a happy number.

It is not a de Polignac number, because 1221010101009 - 2⁷ = 1221010100881 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1221010100982 and 1221010101000.

It is not an unprimeable number, because it can be changed into a prime (1221010101029) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 488012379 + ... + 488014880.

It is an arithmetic number, because the mean of its divisors is an integer number (148030801100).

Almost surely, 2^{1221010101009} is an apocalyptic number.

It is an amenable number.

1221010101009 is a deficient number, since it is larger than the sum of its proper divisors (555359512191).

1221010101009 is a wasteful number, since it uses less digits than its factorization.

1221010101009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 976027404 (or 976027401 counting only the distinct ones).

The product of its (nonzero) digits is 36, while the sum is 18.

The spelling of 1221010101009 in words is "one trillion, two hundred twenty-one billion, ten million, one hundred one thousand, nine".