81873767551 has 8 divisors (see below), whose sum is σ = 83544791904. Its totient is φ = 80207418720.

The previous prime is 81873767543. The next prime is 81873767567. The reversal of 81873767551 is 15576737818.

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

It is a cyclic number.

It is not a de Polignac number, because 81873767551 - 2³ = 81873767543 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81873767251) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1133491 + ... + 1203556.

It is an arithmetic number, because the mean of its divisors is an integer number (10443098988).

Almost surely, 2^81873767551 is an apocalyptic number.

81873767551 is a deficient number, since it is larger than the sum of its proper divisors (1671024353).

81873767551 is a wasteful number, since it uses less digits than its factorization.

81873767551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2337761.

The product of its digits is 9878400, while the sum is 58.

The spelling of 81873767551 in words is "eighty-one billion, eight hundred seventy-three million, seven hundred sixty-seven thousand, five hundred fifty-one".