2121221511 has 24 divisors (see below), whose sum is σ = 3106949664. Its totient is φ = 1394426880.

The previous prime is 2121221477. The next prime is 2121221537. The reversal of 2121221511 is 1151221212.

It is not a de Polignac number, because 2121221511 - 2¹⁸ = 2120959367 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2121221111) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 240990 + ... + 249636.

It is an arithmetic number, because the mean of its divisors is an integer number (129456236).

Almost surely, 2^2121221511 is an apocalyptic number.

2121221511 is a deficient number, since it is larger than the sum of its proper divisors (985728153).

2121221511 is a wasteful number, since it uses less digits than its factorization.

2121221511 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9031 (or 9028 counting only the distinct ones).

The product of its digits is 80, while the sum is 18.

The square root of 2121221511 is about 46056.7205845140. The cubic root of 2121221511 is about 1284.8783385955.

Adding to 2121221511 its reverse (1151221212), we get a palindrome (3272442723).

The spelling of 2121221511 in words is "two billion, one hundred twenty-one million, two hundred twenty-one thousand, five hundred eleven".