80128691 has 2 divisors, whose sum is σ = 80128692. Its totient is φ = 80128690.

The previous prime is 80128627. The next prime is 80128723. The reversal of 80128691 is 19682108.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 80128691 - 2⁶ = 80128627 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (80128891) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40064345 + 40064346.

It is an arithmetic number, because the mean of its divisors is an integer number (40064346).

Almost surely, 2^80128691 is an apocalyptic number.

80128691 is a deficient number, since it is larger than the sum of its proper divisors (1).

80128691 is an equidigital number, since it uses as much as digits as its factorization.

80128691 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 6912, while the sum is 35.

The square root of 80128691 is about 8951.4630647733. The cubic root of 80128691 is about 431.1178611890.

It can be divided in two parts, 801 and 28691, that added together give a palindrome (29492).

The spelling of 80128691 in words is "eighty million, one hundred twenty-eight thousand, six hundred ninety-one".