1221010101011 has 4 divisors (see below), whose sum is σ = 1250790835224. Its totient is φ = 1191229366800.

The previous prime is 1221010100987. The next prime is 1221010101029. The reversal of 1221010101011 is 1101010101221.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 1221010101011 - 2²⁶ = 1220942992147 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1221010100983 and 1221010101001.

It is not an unprimeable number, because it can be changed into a prime (1221010101061) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 14890367045 + ... + 14890367126.

It is an arithmetic number, because the mean of its divisors is an integer number (312697708806).

Almost surely, 2^{1221010101011} is an apocalyptic number.

1221010101011 is a deficient number, since it is larger than the sum of its proper divisors (29780734213).

1221010101011 is an equidigital number, since it uses as much as digits as its factorization.

1221010101011 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29780734212.

The product of its (nonzero) digits is 4, while the sum is 11.

Adding to 1221010101011 its reverse (1101010101221), we get a palindrome (2322020202232).

The spelling of 1221010101011 in words is "one trillion, two hundred twenty-one billion, ten million, one hundred one thousand, eleven".