7821212011 has 2 divisors, whose sum is σ = 7821212012. Its totient is φ = 7821212010.

The previous prime is 7821211949. The next prime is 7821212023. The reversal of 7821212011 is 1102121287.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 7821212011 - 2⁹ = 7821211499 is a prime.

It is a super-2 number, since 2×7821212011² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (7821212071) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3910606005 + 3910606006.

It is an arithmetic number, because the mean of its divisors is an integer number (3910606006).

Almost surely, 2^7821212011 is an apocalyptic number.

7821212011 is a deficient number, since it is larger than the sum of its proper divisors (1).

7821212011 is an equidigital number, since it uses as much as digits as its factorization.

7821212011 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 448, while the sum is 25.

The square root of 7821212011 is about 88437.6164932095. The cubic root of 7821212011 is about 1984.9886119217.

Adding to 7821212011 its reverse (1102121287), we get a palindrome (8923333298).

The spelling of 7821212011 in words is "seven billion, eight hundred twenty-one million, two hundred twelve thousand, eleven".