1201221021 has 128 divisors (see below), whose sum is σ = 2328883200. Its totient is φ = 530012160.

The previous prime is 1201221019. The next prime is 1201221029.

1201221021 is nontrivially palindromic in base 10.

It is not a de Polignac number, because 1201221021 - 2¹ = 1201221019 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1201220988 and 1201221006.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1201221029) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 2110825 + ... + 2111393.

It is an arithmetic number, because the mean of its divisors is an integer number (18194400).

Almost surely, 2^1201221021 is an apocalyptic number.

1201221021 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1201221021 is a deficient number, since it is larger than the sum of its proper divisors (1127662179).

1201221021 is a wasteful number, since it uses less digits than its factorization.

1201221021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 659.

The product of its (nonzero) digits is 16, while the sum is 12.

The square root of 1201221021 is about 34658.6355905711. The cubic root of 1201221021 is about 1063.0188715691.

It can be divided in two parts, 12012 and 21021, that added together give a palindrome (33033).

The spelling of 1201221021 in words is "one billion, two hundred one million, two hundred twenty-one thousand, twenty-one".