80208721 has 2 divisors, whose sum is σ = 80208722. Its totient is φ = 80208720.

The previous prime is 80208719. The next prime is 80208781. The reversal of 80208721 is 12780208.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 57168721 + 23040000 = 7561^2 + 4800^2 .

It is a cyclic number.

It is not a de Polignac number, because 80208721 - 2¹ = 80208719 is a prime.

Together with 80208719, it forms a pair of twin primes.

It is a self number, because there is not a number n which added to its sum of digits gives 80208721.

It is not a weakly prime, because it can be changed into another prime (80208781) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40104360 + 40104361.

It is an arithmetic number, because the mean of its divisors is an integer number (40104361).

Almost surely, 2^80208721 is an apocalyptic number.

It is an amenable number.

80208721 is a deficient number, since it is larger than the sum of its proper divisors (1).

80208721 is an equidigital number, since it uses as much as digits as its factorization.

80208721 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1792, while the sum is 28.

The square root of 80208721 is about 8955.9321681219. The cubic root of 80208721 is about 431.2613423888.

Adding to 80208721 its reverse (12780208), we get a palindrome (92988929).

The spelling of 80208721 in words is "eighty million, two hundred eight thousand, seven hundred twenty-one".