81338438159552 has 224 divisors, whose sum is σ = 198808393482240. Its totient is φ = 32249412264960.

The previous prime is 81338438159543. The next prime is 81338438159581. The reversal of 81338438159552 is 25595183483318.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (224).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 557960849 + ... + 558106607.

Almost surely, 2^{81338438159552} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81338438159552, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (99404196741120).

81338438159552 is an abundant number, since it is smaller than the sum of its proper divisors (117469955322688).

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

81338438159552 is a wasteful number, since it uses less digits than its factorization.

81338438159552 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 147579 (or 147569 counting only the distinct ones).

The product of its digits is 124416000, while the sum is 65.

The spelling of 81338438159552 in words is "eighty-one trillion, three hundred thirty-eight billion, four hundred thirty-eight million, one hundred fifty-nine thousand, five hundred fifty-two".