81494671 has 2 divisors, whose sum is σ = 81494672. Its totient is φ = 81494670.

The previous prime is 81494659. The next prime is 81494687. The reversal of 81494671 is 17649418.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 81494671 - 2¹³ = 81486479 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81491671) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40747335 + 40747336.

It is an arithmetic number, because the mean of its divisors is an integer number (40747336).

Almost surely, 2^81494671 is an apocalyptic number.

81494671 is a deficient number, since it is larger than the sum of its proper divisors (1).

81494671 is an equidigital number, since it uses as much as digits as its factorization.

81494671 is an evil number, because the sum of its binary digits is even.

The product of its digits is 48384, while the sum is 40.

The square root of 81494671 is about 9027.4398917966. The cubic root of 81494671 is about 433.5538730785.

The spelling of 81494671 in words is "eighty-one million, four hundred ninety-four thousand, six hundred seventy-one".