81419776449 has 16 divisors (see below), whose sum is σ = 120436035840. Its totient is φ = 48508956560.

The previous prime is 81419776411. The next prime is 81419776469. The reversal of 81419776449 is 94467791418.

It is a cyclic number.

It is not a de Polignac number, because 81419776449 - 2⁹ = 81419775937 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 81419776392 and 81419776401.

It is not an unprimeable number, because it can be changed into a prime (81419776409) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 20907087 + ... + 20910980.

It is an arithmetic number, because the mean of its divisors is an integer number (7527252240).

Almost surely, 2^81419776449 is an apocalyptic number.

It is an amenable number.

81419776449 is a deficient number, since it is larger than the sum of its proper divisors (39016259391).

81419776449 is a wasteful number, since it uses less digits than its factorization.

81419776449 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41818140.

The product of its digits is 12192768, while the sum is 60.

The spelling of 81419776449 in words is "eighty-one billion, four hundred nineteen million, seven hundred seventy-six thousand, four hundred forty-nine".