81252170496 has 756 divisors, whose sum is σ = 292549879216. Its totient is φ = 22036561920.

The previous prime is 81252170491. The next prime is 81252170501. The reversal of 81252170496 is 69407125218.

81252170496 is a `hidden beast` number, since 8 + 12 + 521 + 70 + 49 + 6 = 666.

It is an interprime number because it is at equal distance from previous prime (81252170491) and next prime (81252170501).

It is a tau number, because it is divible by the number of its divisors (756).

It is a super-2 number, since 2×81252170496² (a number of 23 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (81252170491) by changing a digit.

It is a polite number, since it can be written in 83 ways as a sum of consecutive naturals, for example, 1981760236 + ... + 1981760276.

Almost surely, 2^81252170496 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 81252170496, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (146274939608).

81252170496 is an abundant number, since it is smaller than the sum of its proper divisors (211297708720).

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

81252170496 is an frugal number, since it uses more digits than its factorization.

81252170496 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 160 (or 90 counting only the distinct ones).

The product of its (nonzero) digits is 241920, while the sum is 45.

The spelling of 81252170496 in words is "eighty-one billion, two hundred fifty-two million, one hundred seventy thousand, four hundred ninety-six".