81084552720 has 80 divisors (see below), whose sum is σ = 251742881472. Its totient is φ = 21589793280.

The previous prime is 81084552691. The next prime is 81084552749. The reversal of 81084552720 is 2725548018.

It is an interprime number because it is at equal distance from previous prime (81084552691) and next prime (81084552749).

It is a tau number, because it is divible by the number of its divisors (80).

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 96922 + ... + 414201.

Almost surely, 2^81084552720 is an apocalyptic number.

81084552720 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

81084552720 is an abundant number, since it is smaller than the sum of its proper divisors (170658328752).

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

81084552720 is a wasteful number, since it uses less digits than its factorization.

81084552720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 511800 (or 511794 counting only the distinct ones).

The product of its (nonzero) digits is 179200, while the sum is 42.

The spelling of 81084552720 in words is "eighty-one billion, eighty-four million, five hundred fifty-two thousand, seven hundred twenty".