81629762027520 has 960 divisors, whose sum is σ = 308672025868800. Its totient is φ = 18044650782720.

The previous prime is 81629762027491. The next prime is 81629762027537. The reversal of 81629762027520 is 2572026792618.

It is a tau number, because it is divible by the number of its divisors (960).

It is a super-2 number, since 2×81629762027520² (a number of 29 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 52903279869 + ... + 52903281411.

It is an arithmetic number, because the mean of its divisors is an integer number (321533360280).

Almost surely, 2^{81629762027520} is an apocalyptic number.

81629762027520 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 81629762027520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (154336012934400).

81629762027520 is an abundant number, since it is smaller than the sum of its proper divisors (227042263841280).

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

81629762027520 is an frugal number, since it uses more digits than its factorization.

81629762027520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1658 (or 1591 counting only the distinct ones).

The product of its (nonzero) digits is 10160640, while the sum is 57.

The spelling of 81629762027520 in words is "eighty-one trillion, six hundred twenty-nine billion, seven hundred sixty-two million, twenty-seven thousand, five hundred twenty".