81554131438 has 8 divisors (see below), whose sum is σ = 131741289288. Its totient is φ = 37640368344.

The previous prime is 81554131409. The next prime is 81554131453. The reversal of 81554131438 is 83413145518.

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

It is a junction number, because it is equal to n+sod(n) for n = 81554131394 and 81554131403.

It is a congruent number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 1568348656 + ... + 1568348707.

It is an arithmetic number, because the mean of its divisors is an integer number (16467661161).

Almost surely, 2^81554131438 is an apocalyptic number.

81554131438 is a deficient number, since it is larger than the sum of its proper divisors (50187157850).

81554131438 is a wasteful number, since it uses less digits than its factorization.

81554131438 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3136697378.

The product of its digits is 230400, while the sum is 43.

The spelling of 81554131438 in words is "eighty-one billion, five hundred fifty-four million, one hundred thirty-one thousand, four hundred thirty-eight".