81333900745 has 16 divisors (see below), whose sum is σ = 99141219072. Its totient is φ = 64045883520.

The previous prime is 81333900629. The next prime is 81333900779. The reversal of 81333900745 is 54700933318.

It is a happy number.

It is not a de Polignac number, because 81333900745 - 2⁷ = 81333900617 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 249132 + ... + 474061.

It is an arithmetic number, because the mean of its divisors is an integer number (6196326192).

Almost surely, 2^81333900745 is an apocalyptic number.

It is an amenable number.

81333900745 is a deficient number, since it is larger than the sum of its proper divisors (17807318327).

81333900745 is a wasteful number, since it uses less digits than its factorization.

81333900745 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 723552.

The product of its (nonzero) digits is 272160, while the sum is 43.

The spelling of 81333900745 in words is "eighty-one billion, three hundred thirty-three million, nine hundred thousand, seven hundred forty-five".