80661772391 has 8 divisors (see below), whose sum is σ = 81014967264. Its totient is φ = 80308730880.

The previous prime is 80661772369. The next prime is 80661772421. The reversal of 80661772391 is 19327716608.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 80661772391 - 2⁶ = 80661772327 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (80661772691) 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, 1087895 + ... + 1159671.

It is an arithmetic number, because the mean of its divisors is an integer number (10126870908).

Almost surely, 2^80661772391 is an apocalyptic number.

80661772391 is a deficient number, since it is larger than the sum of its proper divisors (353194873).

80661772391 is a wasteful number, since it uses less digits than its factorization.

80661772391 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 76681.

The product of its (nonzero) digits is 762048, while the sum is 50.

The spelling of 80661772391 in words is "eighty billion, six hundred sixty-one million, seven hundred seventy-two thousand, three hundred ninety-one".