81774401441 has 2 divisors, whose sum is σ = 81774401442. Its totient is φ = 81774401440.

The previous prime is 81774401437. The next prime is 81774401447. The reversal of 81774401441 is 14410447718.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 78879531025 + 2894870416 = 280855^2 + 53804^2 .

It is a cyclic number.

It is not a de Polignac number, because 81774401441 - 2² = 81774401437 is a prime.

It is not a weakly prime, because it can be changed into another prime (81774401447) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40887200720 + 40887200721.

It is an arithmetic number, because the mean of its divisors is an integer number (40887200721).

Almost surely, 2^81774401441 is an apocalyptic number.

It is an amenable number.

81774401441 is a deficient number, since it is larger than the sum of its proper divisors (1).

81774401441 is an equidigital number, since it uses as much as digits as its factorization.

81774401441 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 100352, while the sum is 41.

The spelling of 81774401441 in words is "eighty-one billion, seven hundred seventy-four million, four hundred one thousand, four hundred forty-one".