81490164618240 has 1760 divisors, whose sum is σ = 340033083439104. Its totient is φ = 18352693739520.

The previous prime is 81490164618221. The next prime is 81490164618251. The reversal of 81490164618240 is 4281646109418.

81490164618240 is a `hidden beast` number, since 8 + 1 + 4 + 9 + 0 + 16 + 4 + 618 + 2 + 4 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 159 ways as a sum of consecutive naturals, for example, 50086148307 + ... + 50086149933.

Almost surely, 2^{81490164618240} is an apocalyptic number.

81490164618240 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 81490164618240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (170016541719552).

81490164618240 is an abundant number, since it is smaller than the sum of its proper divisors (258542918820864).

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

81490164618240 is an frugal number, since it uses more digits than its factorization.

81490164618240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1757 (or 1715 counting only the distinct ones).

The product of its (nonzero) digits is 2654208, while the sum is 54.

The spelling of 81490164618240 in words is "eighty-one trillion, four hundred ninety billion, one hundred sixty-four million, six hundred eighteen thousand, two hundred forty".