81195449 has 2 divisors, whose sum is σ = 81195450. Its totient is φ = 81195448.

The previous prime is 81195421. The next prime is 81195463. The reversal of 81195449 is 94459118.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 76650025 + 4545424 = 8755^2 + 2132^2 .

It is a cyclic number.

It is not a de Polignac number, because 81195449 - 2⁸ = 81195193 is a prime.

It is not a weakly prime, because it can be changed into another prime (81195409) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40597724 + 40597725.

It is an arithmetic number, because the mean of its divisors is an integer number (40597725).

Almost surely, 2^81195449 is an apocalyptic number.

It is an amenable number.

81195449 is a deficient number, since it is larger than the sum of its proper divisors (1).

81195449 is an equidigital number, since it uses as much as digits as its factorization.

81195449 is an evil number, because the sum of its binary digits is even.

The product of its digits is 51840, while the sum is 41.

The square root of 81195449 is about 9010.8517355464. The cubic root of 81195449 is about 433.0225992575.

The spelling of 81195449 in words is "eighty-one million, one hundred ninety-five thousand, four hundred forty-nine".