82555499981 has 2 divisors, whose sum is σ = 82555499982. Its totient is φ = 82555499980.

The previous prime is 82555499969. The next prime is 82555500031. The reversal of 82555499981 is 18999455528.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 68779783081 + 13775716900 = 262259^2 + 117370^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-82555499981 is a prime.

It is a super-2 number, since 2×82555499981² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (82555499941) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 41277749990 + 41277749991.

It is an arithmetic number, because the mean of its divisors is an integer number (41277749991).

Almost surely, 2^82555499981 is an apocalyptic number.

It is an amenable number.

82555499981 is a deficient number, since it is larger than the sum of its proper divisors (1).

82555499981 is an equidigital number, since it uses as much as digits as its factorization.

82555499981 is an evil number, because the sum of its binary digits is even.

The product of its digits is 46656000, while the sum is 65.

The spelling of 82555499981 in words is "eighty-two billion, five hundred fifty-five million, four hundred ninety-nine thousand, nine hundred eighty-one".