81598811587 has 2 divisors, whose sum is σ = 81598811588. Its totient is φ = 81598811586.

The previous prime is 81598811579. The next prime is 81598811621. The reversal of 81598811587 is 78511889518.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 81598811587 - 2³ = 81598811579 is a prime.

It is not a weakly prime, because it can be changed into another prime (81598811507) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40799405793 + 40799405794.

It is an arithmetic number, because the mean of its divisors is an integer number (40799405794).

Almost surely, 2^81598811587 is an apocalyptic number.

81598811587 is a deficient number, since it is larger than the sum of its proper divisors (1).

81598811587 is an equidigital number, since it uses as much as digits as its factorization.

81598811587 is an evil number, because the sum of its binary digits is even.

The product of its digits is 6451200, while the sum is 61.

The spelling of 81598811587 in words is "eighty-one billion, five hundred ninety-eight million, eight hundred eleven thousand, five hundred eighty-seven".