81858760 has 16 divisors (see below), whose sum is σ = 184182300. Its totient is φ = 32743488.

The previous prime is 81858743. The next prime is 81858781. The reversal of 81858760 is 6785818.

It can be written as a sum of positive squares in 2 ways, for example, as 70257924 + 11600836 = 8382^2 + 3406^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1023195 + ... + 1023274.

Almost surely, 2^81858760 is an apocalyptic number.

It is an amenable number.

81858760 is an abundant number, since it is smaller than the sum of its proper divisors (102323540).

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

81858760 is a wasteful number, since it uses less digits than its factorization.

81858760 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2046480 (or 2046476 counting only the distinct ones).

The product of its (nonzero) digits is 107520, while the sum is 43.

The square root of 81858760 is about 9047.5831026855. The cubic root of 81858760 is about 434.1985684114.

The spelling of 81858760 in words is "eighty-one million, eight hundred fifty-eight thousand, seven hundred sixty".