81166350 has 48 divisors (see below), whose sum is σ = 201848688. Its totient is φ = 21584640.

The previous prime is 81166307. The next prime is 81166357. The reversal of 81166350 is 5366118.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81166357) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 92112 + ... + 92988.

It is an arithmetic number, because the mean of its divisors is an integer number (4205181).

Almost surely, 2^81166350 is an apocalyptic number.

81166350 is an abundant number, since it is smaller than the sum of its proper divisors (120682338).

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

81166350 is a wasteful number, since it uses less digits than its factorization.

81166350 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1509 (or 1504 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 30.

The square root of 81166350 is about 9009.2369266215. The cubic root of 81166350 is about 432.9708638859.

It can be divided in two parts, 811 and 66350, that added together give a triangular number (67161 = T₃₆₆).

The spelling of 81166350 in words is "eighty-one million, one hundred sixty-six thousand, three hundred fifty".