1221121101 has 32 divisors (see below), whose sum is σ = 1775029248. Its totient is φ = 743592960.

The previous prime is 1221121073. The next prime is 1221121117. The reversal of 1221121101 is 1011211221.

It is not a de Polignac number, because 1221121101 - 2¹⁰ = 1221120077 is a prime.

It is a super-2 number, since 2×1221121101² = 2982273486614904402, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221121001) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1231716 + ... + 1232706.

It is an arithmetic number, because the mean of its divisors is an integer number (55469664).

Almost surely, 2^1221121101 is an apocalyptic number.

It is an amenable number.

1221121101 is a deficient number, since it is larger than the sum of its proper divisors (553908147).

1221121101 is a wasteful number, since it uses less digits than its factorization.

1221121101 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1701.

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

The square root of 1221121101 is about 34944.5432220826. The cubic root of 1221121101 is about 1068.8569331533.

Adding to 1221121101 its reverse (1011211221), we get a palindrome (2232332322).

The spelling of 1221121101 in words is "one billion, two hundred twenty-one million, one hundred twenty-one thousand, one hundred one".