81830545 has 16 divisors (see below), whose sum is σ = 102187008. Its totient is φ = 62838720.

The previous prime is 81830533. The next prime is 81830561. The reversal of 81830545 is 54503818.

It is not a de Polignac number, because 81830545 - 2²¹ = 79733393 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 81830545.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 17607 + ... + 21763.

It is an arithmetic number, because the mean of its divisors is an integer number (6386688).

Almost surely, 2^81830545 is an apocalyptic number.

It is an amenable number.

81830545 is a deficient number, since it is larger than the sum of its proper divisors (20356463).

81830545 is a wasteful number, since it uses less digits than its factorization.

81830545 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4320.

The product of its (nonzero) digits is 19200, while the sum is 34.

The square root of 81830545 is about 9046.0237121069. The cubic root of 81830545 is about 434.1486762947.

The spelling of 81830545 in words is "eighty-one million, eight hundred thirty thousand, five hundred forty-five".