80781409 has 2 divisors, whose sum is σ = 80781410. Its totient is φ = 80781408.

The previous prime is 80781403. The next prime is 80781511. The reversal of 80781409 is 90418708.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 74390625 + 6390784 = 8625^2 + 2528^2 .

It is a cyclic number.

It is not a de Polignac number, because 80781409 - 2⁵ = 80781377 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (80781403) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40390704 + 40390705.

It is an arithmetic number, because the mean of its divisors is an integer number (40390705).

Almost surely, 2^80781409 is an apocalyptic number.

It is an amenable number.

80781409 is a deficient number, since it is larger than the sum of its proper divisors (1).

80781409 is an equidigital number, since it uses as much as digits as its factorization.

80781409 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 16128, while the sum is 37.

The square root of 80781409 is about 8987.8478514047. The cubic root of 80781409 is about 432.2853071455.

The spelling of 80781409 in words is "eighty million, seven hundred eighty-one thousand, four hundred nine".