2421221021 has 2 divisors, whose sum is σ = 2421221022. Its totient is φ = 2421221020.

The previous prime is 2421220973. The next prime is 2421221051. The reversal of 2421221021 is 1201221242.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1396516900 + 1024704121 = 37370^2 + 32011^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2421221021 is a prime.

It is a super-2 number, since 2×2421221021² = 11724622465064564882, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2421221051) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1210610510 + 1210610511.

It is an arithmetic number, because the mean of its divisors is an integer number (1210610511).

Almost surely, 2^2421221021 is an apocalyptic number.

It is an amenable number.

2421221021 is a deficient number, since it is larger than the sum of its proper divisors (1).

2421221021 is an equidigital number, since it uses as much as digits as its factorization.

2421221021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 128, while the sum is 17.

The square root of 2421221021 is about 49205.9043306797. The cubic root of 2421221021 is about 1342.8004514875.

Adding to 2421221021 its reverse (1201221242), we get a palindrome (3622442263).

The spelling of 2421221021 in words is "two billion, four hundred twenty-one million, two hundred twenty-one thousand, twenty-one".