81734420465 has 16 divisors (see below), whose sum is σ = 102372467328. Its totient is φ = 62528247936.

The previous prime is 81734420461. The next prime is 81734420483. The reversal of 81734420465 is 56402443718.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 81734420465 - 2² = 81734420461 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81734420461) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 358349 + ... + 540261.

It is an arithmetic number, because the mean of its divisors is an integer number (6398279208).

Almost surely, 2^81734420465 is an apocalyptic number.

It is an amenable number.

81734420465 is a deficient number, since it is larger than the sum of its proper divisors (20638046863).

81734420465 is a wasteful number, since it uses less digits than its factorization.

81734420465 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 185848.

The product of its (nonzero) digits is 645120, while the sum is 44.

The spelling of 81734420465 in words is "eighty-one billion, seven hundred thirty-four million, four hundred twenty thousand, four hundred sixty-five".