81287827811038 has 4 divisors (see below), whose sum is σ = 121931741716560. Its totient is φ = 40643913905518.

The previous prime is 81287827811023. The next prime is 81287827811063. The reversal of 81287827811038 is 83011872878218.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20321956952758 + ... + 20321956952761.

It is an arithmetic number, because the mean of its divisors is an integer number (30482935429140).

Almost surely, 2^{81287827811038} is an apocalyptic number.

81287827811038 is a deficient number, since it is larger than the sum of its proper divisors (40643913905522).

81287827811038 is a wasteful number, since it uses less digits than its factorization.

81287827811038 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40643913905521.

The product of its (nonzero) digits is 19267584, while the sum is 64.

The spelling of 81287827811038 in words is "eighty-one trillion, two hundred eighty-seven billion, eight hundred twenty-seven million, eight hundred eleven thousand, thirty-eight".