82649581 has 4 divisors (see below), whose sum is σ = 94456672. Its totient is φ = 70842492.

The previous prime is 82649579. The next prime is 82649599. The reversal of 82649581 is 18594628.

It is a happy number.

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 not a de Polignac number, because 82649581 - 2¹ = 82649579 is a prime.

It is a super-2 number, since 2×82649581² = 13661906478951122, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (82649561) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5903535 + ... + 5903548.

It is an arithmetic number, because the mean of its divisors is an integer number (23614168).

Almost surely, 2^82649581 is an apocalyptic number.

It is an amenable number.

82649581 is a deficient number, since it is larger than the sum of its proper divisors (11807091).

82649581 is a wasteful number, since it uses less digits than its factorization.

82649581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11807090.

The product of its digits is 138240, while the sum is 43.

The square root of 82649581 is about 9091.1814963733. The cubic root of 82649581 is about 435.5923247189.

The spelling of 82649581 in words is "eighty-two million, six hundred forty-nine thousand, five hundred eighty-one".