81372801687 has 8 divisors (see below), whose sum is σ = 108537159936. Its totient is φ = 54228488952.

The previous prime is 81372801673. The next prime is 81372801733. The reversal of 81372801687 is 78610827318.

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

It is a de Polignac number, because none of the positive numbers 2^k-81372801687 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81372801637) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5001903 + ... + 5018144.

It is an arithmetic number, because the mean of its divisors is an integer number (13567144992).

Almost surely, 2^81372801687 is an apocalyptic number.

81372801687 is a deficient number, since it is larger than the sum of its proper divisors (27164358249).

81372801687 is a wasteful number, since it uses less digits than its factorization.

81372801687 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10022757.

The product of its (nonzero) digits is 903168, while the sum is 51.

The spelling of 81372801687 in words is "eighty-one billion, three hundred seventy-two million, eight hundred one thousand, six hundred eighty-seven".