81962075520 has 1152 divisors, whose sum is σ = 338449194720. Its totient is φ = 18101698560.

The previous prime is 81962075519. The next prime is 81962075527. The reversal of 81962075520 is 2557026918.

81962075520 is a `hidden beast` number, since 8 + 1 + 96 + 2 + 0 + 7 + 552 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (1152).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81962075527) by changing a digit.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 1223314527 + ... + 1223314593.

Almost surely, 2^81962075520 is an apocalyptic number.

81962075520 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 81962075520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (169224597360).

81962075520 is an abundant number, since it is smaller than the sum of its proper divisors (256487119200).

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

81962075520 is a wasteful number, since it uses less digits than its factorization.

81962075520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 184 (or 138 counting only the distinct ones).

The product of its (nonzero) digits is 302400, while the sum is 45.

The spelling of 81962075520 in words is "eighty-one billion, nine hundred sixty-two million, seventy-five thousand, five hundred twenty".