81705276 has 36 divisors (see below), whose sum is σ = 209154400. Its totient is φ = 26889408.

The previous prime is 81705271. The next prime is 81705329. The reversal of 81705276 is 67250718.

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 81705276.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81705271) 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, 11521 + ... + 17208.

Almost surely, 2^81705276 is an apocalyptic number.

It is an amenable number.

81705276 is an abundant number, since it is smaller than the sum of its proper divisors (127449124).

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

81705276 is a wasteful number, since it uses less digits than its factorization.

81705276 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28818 (or 28813 counting only the distinct ones).

The product of its (nonzero) digits is 23520, while the sum is 36.

The square root of 81705276 is about 9039.0970788016. The cubic root of 81705276 is about 433.9270266005.

The spelling of 81705276 in words is "eighty-one million, seven hundred five thousand, two hundred seventy-six".