81614517889 has 2 divisors, whose sum is σ = 81614517890. Its totient is φ = 81614517888.

The previous prime is 81614517871. The next prime is 81614517913. The reversal of 81614517889 is 98871541618.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 81122432400 + 492085489 = 284820^2 + 22183^2 .

It is a cyclic number.

It is not a de Polignac number, because 81614517889 - 2⁵ = 81614517857 is a prime.

It is not a weakly prime, because it can be changed into another prime (81614517289) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40807258944 + 40807258945.

It is an arithmetic number, because the mean of its divisors is an integer number (40807258945).

Almost surely, 2^81614517889 is an apocalyptic number.

It is an amenable number.

81614517889 is a deficient number, since it is larger than the sum of its proper divisors (1).

81614517889 is an equidigital number, since it uses as much as digits as its factorization.

81614517889 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3870720, while the sum is 58.

The spelling of 81614517889 in words is "eighty-one billion, six hundred fourteen million, five hundred seventeen thousand, eight hundred eighty-nine".