82639540 has 12 divisors (see below), whose sum is σ = 173543076. Its totient is φ = 33055808.

The previous prime is 82639523. The next prime is 82639541. The reversal of 82639540 is 4593628.

It can be written as a sum of positive squares in 2 ways, for example, as 33246756 + 49392784 = 5766^2 + 7028^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 82639540.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (82639541) 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, 2065969 + ... + 2066008.

It is an arithmetic number, because the mean of its divisors is an integer number (14461923).

Almost surely, 2^82639540 is an apocalyptic number.

It is an amenable number.

82639540 is an abundant number, since it is smaller than the sum of its proper divisors (90903536).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

82639540 is a wasteful number, since it uses less digits than its factorization.

82639540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4131986 (or 4131984 counting only the distinct ones).

The product of its (nonzero) digits is 51840, while the sum is 37.

The square root of 82639540 is about 9090.6292411472. The cubic root of 82639540 is about 435.5746841388.

The spelling of 82639540 in words is "eighty-two million, six hundred thirty-nine thousand, five hundred forty".