82780791 has 8 divisors (see below), whose sum is σ = 111446400. Its totient is φ = 54651192.

The previous prime is 82780787. The next prime is 82780793. The reversal of 82780791 is 19708728.

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

It is not a de Polignac number, because 82780791 - 2² = 82780787 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (82780793) 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, 133641 + ... + 134258.

It is an arithmetic number, because the mean of its divisors is an integer number (13930800).

Almost surely, 2^82780791 is an apocalyptic number.

82780791 is a deficient number, since it is larger than the sum of its proper divisors (28665609).

82780791 is a wasteful number, since it uses less digits than its factorization.

82780791 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 268005.

The product of its (nonzero) digits is 56448, while the sum is 42.

The square root of 82780791 is about 9098.3949683447. The cubic root of 82780791 is about 435.8227104429.

It can be divided in two parts, 827 and 80791, that added together give a palindrome (81618).

The spelling of 82780791 in words is "eighty-two million, seven hundred eighty thousand, seven hundred ninety-one".