81598523 has 2 divisors, whose sum is σ = 81598524. Its totient is φ = 81598522.

The previous prime is 81598519. The next prime is 81598529. The reversal of 81598523 is 32589518.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 81598523 - 2² = 81598519 is a prime.

It is not a weakly prime, because it can be changed into another prime (81598529) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40799261 + 40799262.

It is an arithmetic number, because the mean of its divisors is an integer number (40799262).

Almost surely, 2^81598523 is an apocalyptic number.

81598523 is a deficient number, since it is larger than the sum of its proper divisors (1).

81598523 is an equidigital number, since it uses as much as digits as its factorization.

81598523 is an evil number, because the sum of its binary digits is even.

The product of its digits is 86400, while the sum is 41.

The square root of 81598523 is about 9033.1900788149. The cubic root of 81598523 is about 433.7379600619.

The spelling of 81598523 in words is "eighty-one million, five hundred ninety-eight thousand, five hundred twenty-three".