81828873 has 60 divisors (see below), whose sum is σ = 145250820. Its totient is φ = 45759168.

The previous prime is 81828869. The next prime is 81828881. The reversal of 81828873 is 37882818.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 38900169 + 42928704 = 6237^2 + 6552^2 .

It is not a de Polignac number, because 81828873 - 2² = 81828869 is a prime.

It is not an unprimeable number, because it can be changed into a prime (81828853) by changing a digit.

It is a polite number, since it can be written in 59 ways as a sum of consecutive naturals, for example, 210163 + ... + 210551.

It is an arithmetic number, because the mean of its divisors is an integer number (2420847).

Almost surely, 2^81828873 is an apocalyptic number.

It is an amenable number.

81828873 is a deficient number, since it is larger than the sum of its proper divisors (63421947).

81828873 is a wasteful number, since it uses less digits than its factorization.

81828873 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 468 (or 452 counting only the distinct ones).

The product of its digits is 172032, while the sum is 45.

The square root of 81828873 is about 9045.9312953394. The cubic root of 81828873 is about 434.1457193649.

The spelling of 81828873 in words is "eighty-one million, eight hundred twenty-eight thousand, eight hundred seventy-three".