80361821 has 2 divisors, whose sum is σ = 80361822. Its totient is φ = 80361820.

The previous prime is 80361803. The next prime is 80361823. The reversal of 80361821 is 12816308.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 53436100 + 26925721 = 7310^2 + 5189^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-80361821 is a prime.

It is a Sophie Germain prime.

Together with 80361823, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (80361823) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40180910 + 40180911.

It is an arithmetic number, because the mean of its divisors is an integer number (40180911).

Almost surely, 2^80361821 is an apocalyptic number.

It is an amenable number.

80361821 is a deficient number, since it is larger than the sum of its proper divisors (1).

80361821 is an equidigital number, since it uses as much as digits as its factorization.

80361821 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2304, while the sum is 29.

The square root of 80361821 is about 8964.4755005522. The cubic root of 80361821 is about 431.5355608929.

The spelling of 80361821 in words is "eighty million, three hundred sixty-one thousand, eight hundred twenty-one".