81564389306 has 8 divisors (see below), whose sum is σ = 123280527744. Its totient is φ = 40470880060.

The previous prime is 81564389293. The next prime is 81564389351. The reversal of 81564389306 is 60398346518.

It is a sphenic number, since it is the product of 3 distinct primes.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 155656970 + ... + 155657493.

It is an arithmetic number, because the mean of its divisors is an integer number (15410065968).

Almost surely, 2^81564389306 is an apocalyptic number.

81564389306 is a deficient number, since it is larger than the sum of its proper divisors (41716138438).

81564389306 is a wasteful number, since it uses less digits than its factorization.

81564389306 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 311314596.

The product of its (nonzero) digits is 3732480, while the sum is 53.

The spelling of 81564389306 in words is "eighty-one billion, five hundred sixty-four million, three hundred eighty-nine thousand, three hundred six".