81853185960 has 640 divisors, whose sum is σ = 343335041280. Its totient is φ = 17029066752.

The previous prime is 81853185917. The next prime is 81853185971. The reversal of 81853185960 is 6958135818.

81853185960 is a `hidden beast` number, since 8 + 18 + 5 + 31 + 8 + 596 + 0 = 666.

It is a super-2 number, since 2×81853185960² (a number of 23 digits) contains 22 as substring.

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

It is a junction number, because it is equal to n+sod(n) for n = 81853185897 and 81853185906.

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, 21521419 + ... + 21525221.

It is an arithmetic number, because the mean of its divisors is an integer number (536461002).

Almost surely, 2^81853185960 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81853185960, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (171667520640).

81853185960 is an abundant number, since it is smaller than the sum of its proper divisors (261481855320).

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

81853185960 is a wasteful number, since it uses less digits than its factorization.

81853185960 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3919 (or 3906 counting only the distinct ones).

The product of its (nonzero) digits is 2073600, while the sum is 54.

The spelling of 81853185960 in words is "eighty-one billion, eight hundred fifty-three million, one hundred eighty-five thousand, nine hundred sixty".