81648000869 has 2 divisors, whose sum is σ = 81648000870. Its totient is φ = 81648000868.

The previous prime is 81648000737. The next prime is 81648000881. The reversal of 81648000869 is 96800084618.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 78365283844 + 3282717025 = 279938^2 + 57295^2 .

It is a cyclic number.

It is not a de Polignac number, because 81648000869 - 2²⁸ = 81379565413 is a prime.

It is a super-2 number, since 2×81648000869² (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 (84648000869) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40824000434 + 40824000435.

It is an arithmetic number, because the mean of its divisors is an integer number (40824000435).

Almost surely, 2^81648000869 is an apocalyptic number.

It is an amenable number.

81648000869 is a deficient number, since it is larger than the sum of its proper divisors (1).

81648000869 is an equidigital number, since it uses as much as digits as its factorization.

81648000869 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 663552, while the sum is 50.

The spelling of 81648000869 in words is "eighty-one billion, six hundred forty-eight million, eight hundred sixty-nine", and thus it is an aban number.