81365460 has 192 divisors, whose sum is σ = 263983104. Its totient is φ = 18547200.

The previous prime is 81365437. The next prime is 81365461. The reversal of 81365460 is 6456318.

81365460 is nontrivially palindromic in base 16.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81365461) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1333830 + ... + 1333890.

It is an arithmetic number, because the mean of its divisors is an integer number (1374912).

Almost surely, 2^81365460 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 81365460, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (131991552).

81365460 is an abundant number, since it is smaller than the sum of its proper divisors (182617644).

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

81365460 is a wasteful number, since it uses less digits than its factorization.

81365460 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 174 (or 172 counting only the distinct ones).

The product of its (nonzero) digits is 17280, while the sum is 33.

The square root of 81365460 is about 9020.2804834440. The cubic root of 81365460 is about 433.3246165242.

The spelling of 81365460 in words is "eighty-one million, three hundred sixty-five thousand, four hundred sixty".