82047257781 has 4 divisors (see below), whose sum is σ = 109396343712. Its totient is φ = 54698171852.

The previous prime is 82047257759. The next prime is 82047257783. The reversal of 82047257781 is 18775274028.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 82047257781 - 2⁷ = 82047257653 is a prime.

It is a super-2 number, since 2×82047257781² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (82047257783) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13674542961 + ... + 13674542966.

It is an arithmetic number, because the mean of its divisors is an integer number (27349085928).

Almost surely, 2^82047257781 is an apocalyptic number.

It is an amenable number.

82047257781 is a deficient number, since it is larger than the sum of its proper divisors (27349085931).

82047257781 is a wasteful number, since it uses less digits than its factorization.

82047257781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27349085930.

The product of its (nonzero) digits is 1756160, while the sum is 51.

The spelling of 82047257781 in words is "eighty-two billion, forty-seven million, two hundred fifty-seven thousand, seven hundred eighty-one".