1011121221 has 32 divisors (see below), whose sum is σ = 1556881920. Its totient is φ = 577886400.

The previous prime is 1011121219. The next prime is 1011121261. The reversal of 1011121221 is 1221211101.

It is not a de Polignac number, because 1011121221 - 2¹ = 1011121219 is a prime.

It is a super-2 number, since 2×1011121221² = 2044732247113061682, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1011121197 and 1011121206.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1011121261) 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, 28866 + ... + 53436.

It is an arithmetic number, because the mean of its divisors is an integer number (48652560).

Almost surely, 2^1011121221 is an apocalyptic number.

1011121221 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1011121221 is a deficient number, since it is larger than the sum of its proper divisors (545760699).

1011121221 is a wasteful number, since it uses less digits than its factorization.

1011121221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24657.

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

The square root of 1011121221 is about 31798.1323508158. The cubic root of 1011121221 is about 1003.6934155539.

Adding to 1011121221 its reverse (1221211101), we get a palindrome (2232332322).

The spelling of 1011121221 in words is "one billion, eleven million, one hundred twenty-one thousand, two hundred twenty-one".