81441803 has 2 divisors, whose sum is σ = 81441804. Its totient is φ = 81441802.

The previous prime is 81441799. The next prime is 81441821. The reversal of 81441803 is 30814418.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 81441803 - 2² = 81441799 is a prime.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (81441823) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40720901 + 40720902.

It is an arithmetic number, because the mean of its divisors is an integer number (40720902).

Almost surely, 2^81441803 is an apocalyptic number.

81441803 is a deficient number, since it is larger than the sum of its proper divisors (1).

81441803 is an equidigital number, since it uses as much as digits as its factorization.

81441803 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3072, while the sum is 29.

The square root of 81441803 is about 9024.5112333023. The cubic root of 81441803 is about 433.4600997303.

The spelling of 81441803 in words is "eighty-one million, four hundred forty-one thousand, eight hundred three".