81534747434788 has 48 divisors (see below), whose sum is σ = 145706683510080. Its totient is φ = 39913238744064.

The previous prime is 81534747434779. The next prime is 81534747434807. The reversal of 81534747434788 is 88743474743518.

It is a Smith number, since the sum of its digits (73) coincides with the sum of the digits of its prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 81534747434788.

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, 233062183 + ... + 233411761.

It is an arithmetic number, because the mean of its divisors is an integer number (3035555906460).

Almost surely, 2^{81534747434788} is an apocalyptic number.

It is an amenable number.

81534747434788 is a deficient number, since it is larger than the sum of its proper divisors (64171936075292).

81534747434788 is a wasteful number, since it uses less digits than its factorization.

81534747434788 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 355996 (or 355994 counting only the distinct ones).

The product of its digits is 2023096320, while the sum is 73.

The spelling of 81534747434788 in words is "eighty-one trillion, five hundred thirty-four billion, seven hundred forty-seven million, four hundred thirty-four thousand, seven hundred eighty-eight".