81589709474 has 48 divisors (see below), whose sum is σ = 155148981120. Its totient is φ = 31489960320.

The previous prime is 81589709473. The next prime is 81589709483. The reversal of 81589709474 is 47490798518.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (81589709473) 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 23 ways as a sum of consecutive naturals, for example, 323534 + ... + 517545.

It is an arithmetic number, because the mean of its divisors is an integer number (3232270440).

Almost surely, 2^81589709474 is an apocalyptic number.

81589709474 is a deficient number, since it is larger than the sum of its proper divisors (73559271646).

81589709474 is a wasteful number, since it uses less digits than its factorization.

81589709474 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 841155 (or 841142 counting only the distinct ones).

The product of its (nonzero) digits is 20321280, while the sum is 62.

The spelling of 81589709474 in words is "eighty-one billion, five hundred eighty-nine million, seven hundred nine thousand, four hundred seventy-four".