81333900747 has 12 divisors (see below), whose sum is σ = 128162510424. Its totient is φ = 49293273120.

The previous prime is 81333900629. The next prime is 81333900779. The reversal of 81333900747 is 74700933318.

It is not a de Polignac number, because 81333900747 - 2⁷ = 81333900619 is a prime.

It is not an unprimeable number, because it can be changed into a prime (81333900787) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 410777178 + ... + 410777375.

It is an arithmetic number, because the mean of its divisors is an integer number (10680209202).

Almost surely, 2^81333900747 is an apocalyptic number.

81333900747 is a deficient number, since it is larger than the sum of its proper divisors (46828609677).

81333900747 is a wasteful number, since it uses less digits than its factorization.

81333900747 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 821554570 (or 821554567 counting only the distinct ones).

The product of its (nonzero) digits is 381024, while the sum is 45.

The spelling of 81333900747 in words is "eighty-one billion, three hundred thirty-three million, nine hundred thousand, seven hundred forty-seven".