81867202523 has 2 divisors, whose sum is σ = 81867202524. Its totient is φ = 81867202522.

The previous prime is 81867202513. The next prime is 81867202597. The reversal of 81867202523 is 32520276818.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 81867202523 - 2¹⁰ = 81867201499 is a prime.

It is not a weakly prime, because it can be changed into another prime (81867202513) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40933601261 + 40933601262.

It is an arithmetic number, because the mean of its divisors is an integer number (40933601262).

Almost surely, 2^81867202523 is an apocalyptic number.

81867202523 is a deficient number, since it is larger than the sum of its proper divisors (1).

81867202523 is an equidigital number, since it uses as much as digits as its factorization.

81867202523 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 322560, while the sum is 44.

The spelling of 81867202523 in words is "eighty-one billion, eight hundred sixty-seven million, two hundred two thousand, five hundred twenty-three".