81018974453760 has 2160 divisors, whose sum is σ = 342215368814592. Its totient is φ = 17657914982400.

The previous prime is 81018974453759. The next prime is 81018974453783. The reversal of 81018974453760 is 6735447981018.

81018974453760 is a `hidden beast` number, since 8 + 1 + 0 + 1 + 8 + 97 + 4 + 4 + 537 + 6 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 81754766865 + ... + 81754767855.

Almost surely, 2^{81018974453760} is an apocalyptic number.

81018974453760 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 81018974453760, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (171107684407296).

81018974453760 is an abundant number, since it is smaller than the sum of its proper divisors (261196394360832).

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

81018974453760 is a wasteful number, since it uses less digits than its factorization.

81018974453760 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1148 (or 1112 counting only the distinct ones).

The product of its (nonzero) digits is 40642560, while the sum is 63.

The spelling of 81018974453760 in words is "eighty-one trillion, eighteen billion, nine hundred seventy-four million, four hundred fifty-three thousand, seven hundred sixty".