81426440000 has 280 divisors, whose sum is σ = 213996349248. Its totient is φ = 30666240000.

The previous prime is 81426439999. The next prime is 81426440083. The reversal of 81426440000 is 4462418.

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 39 ways as a sum of consecutive naturals, for example, 61639340 + ... + 61640660.

Almost surely, 2^81426440000 is an apocalyptic number.

81426440000 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81426440000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (106998174624).

81426440000 is an abundant number, since it is smaller than the sum of its proper divisors (132569909248).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81426440000 is a wasteful number, since it uses less digits than its factorization.

81426440000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1443 (or 1418 counting only the distinct ones).

The product of its (nonzero) digits is 6144, while the sum is 29.

The spelling of 81426440000 in words is "eighty-one billion, four hundred twenty-six million, four hundred forty thousand".