80191720 has 96 divisors (see below), whose sum is σ = 219271680. Its totient is φ = 25850880.

The previous prime is 80191687. The next prime is 80191747. The reversal of 80191720 is 2719108.

It is a Harshad number since it is a multiple of its sum of digits (28).

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 80425 + ... + 81415.

It is an arithmetic number, because the mean of its divisors is an integer number (2284080).

Almost surely, 2^80191720 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 80191720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (109635840).

80191720 is an abundant number, since it is smaller than the sum of its proper divisors (139079960).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

80191720 is a wasteful number, since it uses less digits than its factorization.

80191720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1043 (or 1022 counting only the distinct ones).

The product of its (nonzero) digits is 1008, while the sum is 28.

The square root of 80191720 is about 8954.9829703914. The cubic root of 80191720 is about 431.2308702569.

The spelling of 80191720 in words is "eighty million, one hundred ninety-one thousand, seven hundred twenty".