2120001221 has 16 divisors (see below), whose sum is σ = 2305787904. Its totient is φ = 1937525184.

The previous prime is 2120001197. The next prime is 2120001229. The reversal of 2120001221 is 1221000212.

It is a happy number.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2120001221 is a prime.

It is a super-3 number, since 3×2120001221³ (a number of 29 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2120001229) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1060595 + ... + 1062591.

It is an arithmetic number, because the mean of its divisors is an integer number (144111744).

Almost surely, 2^2120001221 is an apocalyptic number.

It is an amenable number.

2120001221 is a deficient number, since it is larger than the sum of its proper divisors (185786683).

2120001221 is a wasteful number, since it uses less digits than its factorization.

2120001221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2780.

The product of its (nonzero) digits is 16, while the sum is 11.

The square root of 2120001221 is about 46043.4709920962. The cubic root of 2120001221 is about 1284.6319043375.

Adding to 2120001221 its reverse (1221000212), we get a palindrome (3341001433).

The spelling of 2120001221 in words is "two billion, one hundred twenty million, one thousand, two hundred twenty-one".