80720091 has 8 divisors (see below), whose sum is σ = 119585360. Its totient is φ = 53813376.

The previous prime is 80720089. The next prime is 80720119. The reversal of 80720091 is 19002708.

It is not a de Polignac number, because 80720091 - 2¹ = 80720089 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27), and also a Moran number because the ratio is a prime number: 2989633 = 80720091 / (8 + 0 + 7 + 2 + 0 + 0 + 9 + 1).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (80720011) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1494790 + ... + 1494843.

It is an arithmetic number, because the mean of its divisors is an integer number (14948170).

Almost surely, 2^80720091 is an apocalyptic number.

80720091 is a deficient number, since it is larger than the sum of its proper divisors (38865269).

80720091 is a wasteful number, since it uses less digits than its factorization.

80720091 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2989642 (or 2989636 counting only the distinct ones).

The product of its (nonzero) digits is 1008, while the sum is 27.

The square root of 80720091 is about 8984.4360424013. The cubic root of 80720091 is about 432.1759025172.

Adding to 80720091 its reverse (19002708), we get a palindrome (99722799).

The spelling of 80720091 in words is "eighty million, seven hundred twenty thousand, ninety-one".