7720081 has 2 divisors, whose sum is σ = 7720082. Its totient is φ = 7720080.

The previous prime is 7720067. The next prime is 7720093. The reversal of 7720081 is 1800277.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 5363856 + 2356225 = 2316^2 + 1535^2 .

It is an emirp because it is prime and its reverse (1800277) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 7720081 - 2⁵ = 7720049 is a prime.

It is a super-2 number, since 2×7720081² = 119199301293122, which contains 22 as substring.

It is an Ulam number.

It is not a weakly prime, because it can be changed into another prime (7720001) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3860040 + 3860041.

It is an arithmetic number, because the mean of its divisors is an integer number (3860041).

Almost surely, 2^7720081 is an apocalyptic number.

It is an amenable number.

7720081 is a deficient number, since it is larger than the sum of its proper divisors (1).

7720081 is an equidigital number, since it uses as much as digits as its factorization.

7720081 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 784, while the sum is 25.

The square root of 7720081 is about 2778.5033741207. The cubic root of 7720081 is about 197.6395936685.

The spelling of 7720081 in words is "seven million, seven hundred twenty thousand, eighty-one".