81650826 has 12 divisors (see below), whose sum is σ = 176910162. Its totient is φ = 27216936.

The previous prime is 81650791. The next prime is 81650827. The reversal of 81650826 is 62805618.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 55487601 + 26163225 = 7449^2 + 5115^2 .

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (81650827) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 2268061 + ... + 2268096.

Almost surely, 2^81650826 is an apocalyptic number.

81650826 is an abundant number, since it is smaller than the sum of its proper divisors (95259336).

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

81650826 is a wasteful number, since it uses less digits than its factorization.

81650826 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4536165 (or 4536162 counting only the distinct ones).

The product of its (nonzero) digits is 23040, while the sum is 36.

The square root of 81650826 is about 9036.0846609580. The cubic root of 81650826 is about 433.8306126834.

The spelling of 81650826 in words is "eighty-one million, six hundred fifty thousand, eight hundred twenty-six".