81830845 has 8 divisors (see below), whose sum is σ = 98696664. Its totient is φ = 65131584.

The previous prime is 81830839. The next prime is 81830851. The reversal of 81830845 is 54803818.

It is an interprime number because it is at equal distance from previous prime (81830839) and next prime (81830851).

It can be written as a sum of positive squares in 4 ways, for example, as 29224836 + 52606009 = 5406^2 + 7253^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 81830845 - 2¹⁹ = 81306557 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 40554 + ... + 42523.

It is an arithmetic number, because the mean of its divisors is an integer number (12337083).

Almost surely, 2^81830845 is an apocalyptic number.

It is an amenable number.

81830845 is a deficient number, since it is larger than the sum of its proper divisors (16865819).

81830845 is a wasteful number, since it uses less digits than its factorization.

81830845 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 83279.

The product of its (nonzero) digits is 30720, while the sum is 37.

The square root of 81830845 is about 9046.0402939629. The cubic root of 81830845 is about 434.1492068400.

The spelling of 81830845 in words is "eighty-one million, eight hundred thirty thousand, eight hundred forty-five".