82815533557 has 4 divisors (see below), whose sum is σ = 83746045260. Its totient is φ = 81885021856.

The previous prime is 82815533483. The next prime is 82815533569. The reversal of 82815533557 is 75533551828.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 35413970596 + 47401562961 = 188186^2 + 217719^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-82815533557 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (82815533357) 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, 465255718 + ... + 465255895.

It is an arithmetic number, because the mean of its divisors is an integer number (20936511315).

Almost surely, 2^82815533557 is an apocalyptic number.

It is an amenable number.

82815533557 is a deficient number, since it is larger than the sum of its proper divisors (930511703).

82815533557 is an equidigital number, since it uses as much as digits as its factorization.

82815533557 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 930511702.

The product of its digits is 5040000, while the sum is 52.

The spelling of 82815533557 in words is "eighty-two billion, eight hundred fifteen million, five hundred thirty-three thousand, five hundred fifty-seven".