81826563 has 16 divisors (see below), whose sum is σ = 134279936. Its totient is φ = 43161120.

The previous prime is 81826543. The next prime is 81826567. The reversal of 81826563 is 36562818.

It is a happy number.

It is not a de Polignac number, because 81826563 - 2¹² = 81822467 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is not an unprimeable number, because it can be changed into a prime (81826567) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 149593 + ... + 150138.

It is an arithmetic number, because the mean of its divisors is an integer number (8392496).

Almost surely, 2^81826563 is an apocalyptic number.

81826563 is a deficient number, since it is larger than the sum of its proper divisors (52453373).

81826563 is a wasteful number, since it uses less digits than its factorization.

81826563 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 299754.

The product of its digits is 69120, while the sum is 39.

The square root of 81826563 is about 9045.8036127256. The cubic root of 81826563 is about 434.1416340666.

The spelling of 81826563 in words is "eighty-one million, eight hundred twenty-six thousand, five hundred sixty-three".