81504767 has 2 divisors, whose sum is σ = 81504768. Its totient is φ = 81504766.

The previous prime is 81504743. The next prime is 81504781. The reversal of 81504767 is 76740518.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 81504767 - 2¹⁴ = 81488383 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 81504767.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81504067) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40752383 + 40752384.

It is an arithmetic number, because the mean of its divisors is an integer number (40752384).

Almost surely, 2^81504767 is an apocalyptic number.

81504767 is a deficient number, since it is larger than the sum of its proper divisors (1).

81504767 is an equidigital number, since it uses as much as digits as its factorization.

81504767 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 47040, while the sum is 38.

The square root of 81504767 is about 9027.9990584847. Note that the first 3 decimals coincide. The cubic root of 81504767 is about 433.5717760044.

The spelling of 81504767 in words is "eighty-one million, five hundred four thousand, seven hundred sixty-seven".