82565781 has 8 divisors (see below), whose sum is σ = 110287584. Its totient is φ = 54943920.

The previous prime is 82565779. The next prime is 82565809. The reversal of 82565781 is 18756528.

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

It is not a de Polignac number, because 82565781 - 2¹ = 82565779 is a prime.

It is a super-2 number, since 2×82565781² = 13634216384279922, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (82565771) 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, 23035 + ... + 26376.

It is an arithmetic number, because the mean of its divisors is an integer number (13785948).

Almost surely, 2^82565781 is an apocalyptic number.

It is an amenable number.

82565781 is a deficient number, since it is larger than the sum of its proper divisors (27721803).

82565781 is a wasteful number, since it uses less digits than its factorization.

82565781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 49971.

The product of its digits is 134400, while the sum is 42.

The square root of 82565781 is about 9086.5714656299. The cubic root of 82565781 is about 435.4450564560.

The spelling of 82565781 in words is "eighty-two million, five hundred sixty-five thousand, seven hundred eighty-one".