81306486 has 24 divisors (see below), whose sum is σ = 177455304. Its totient is φ = 26903520.

The previous prime is 81306457. The next prime is 81306487. The reversal of 81306486 is 68460318.

It is a happy number.

81306486 is a `hidden beast` number, since 8 + 1 + 3 + 0 + 648 + 6 = 666.

It is a super-2 number, since 2×81306486² = 13221489331336392, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 81306486.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81306487) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 14020 + ... + 18951.

It is an arithmetic number, because the mean of its divisors is an integer number (7393971).

Almost surely, 2^81306486 is an apocalyptic number.

81306486 is an abundant number, since it is smaller than the sum of its proper divisors (96148818).

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

81306486 is a wasteful number, since it uses less digits than its factorization.

81306486 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33116 (or 33113 counting only the distinct ones).

The product of its (nonzero) digits is 27648, while the sum is 36.

The square root of 81306486 is about 9017.0109238040. The cubic root of 81306486 is about 433.2198994345.

The spelling of 81306486 in words is "eighty-one million, three hundred six thousand, four hundred eighty-six".