81491076554160 has 960 divisors, whose sum is σ = 333692554309632. Its totient is φ = 16015377825792.

The previous prime is 81491076554137. The next prime is 81491076554201. The reversal of 81491076554160 is 6145567019418.

It is a self number, because there is not a number n which added to its sum of digits gives 81491076554160.

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 612174169 + ... + 612307271.

Almost surely, 2^{81491076554160} is an apocalyptic number.

81491076554160 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 81491076554160, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (166846277154816).

81491076554160 is an abundant number, since it is smaller than the sum of its proper divisors (252201477755472).

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

81491076554160 is a wasteful number, since it uses less digits than its factorization.

81491076554160 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 133270 (or 133247 counting only the distinct ones).

The product of its (nonzero) digits is 7257600, while the sum is 57.

The spelling of 81491076554160 in words is "eighty-one trillion, four hundred ninety-one billion, seventy-six million, five hundred fifty-four thousand, one hundred sixty".