82378717021 has 2 divisors, whose sum is σ = 82378717022. Its totient is φ = 82378717020.

The previous prime is 82378716991. The next prime is 82378717049. The reversal of 82378717021 is 12071787328.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 82122364900 + 256352121 = 286570^2 + 16011^2 .

It is a cyclic number.

It is not a de Polignac number, because 82378717021 - 2⁹ = 82378716509 is a prime.

It is a super-2 number, since 2×82378717021² (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 (82378717051) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 41189358510 + 41189358511.

It is an arithmetic number, because the mean of its divisors is an integer number (41189358511).

Almost surely, 2^82378717021 is an apocalyptic number.

It is an amenable number.

82378717021 is a deficient number, since it is larger than the sum of its proper divisors (1).

82378717021 is an equidigital number, since it uses as much as digits as its factorization.

82378717021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 263424, while the sum is 46.

The spelling of 82378717021 in words is "eighty-two billion, three hundred seventy-eight million, seven hundred seventeen thousand, twenty-one".