81788963 has 2 divisors, whose sum is σ = 81788964. Its totient is φ = 81788962.

The previous prime is 81788929. The next prime is 81789007. The reversal of 81788963 is 36988718.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 81788963 - 2¹⁰ = 81787939 is a prime.

It is not a weakly prime, because it can be changed into another prime (81788923) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40894481 + 40894482.

It is an arithmetic number, because the mean of its divisors is an integer number (40894482).

Almost surely, 2^81788963 is an apocalyptic number.

81788963 is a deficient number, since it is larger than the sum of its proper divisors (1).

81788963 is an equidigital number, since it uses as much as digits as its factorization.

81788963 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 580608, while the sum is 50.

The square root of 81788963 is about 9043.7250621633. The cubic root of 81788963 is about 434.0751266238.

The spelling of 81788963 in words is "eighty-one million, seven hundred eighty-eight thousand, nine hundred sixty-three".