81873535 has 8 divisors (see below), whose sum is σ = 98322336. Its totient is φ = 65449440.

The previous prime is 81873521. The next prime is 81873541. The reversal of 81873535 is 53537818.

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

It is not a de Polignac number, because 81873535 - 2¹⁵ = 81840767 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, 2137 + ... + 12973.

It is an arithmetic number, because the mean of its divisors is an integer number (12290292).

Almost surely, 2^81873535 is an apocalyptic number.

81873535 is a deficient number, since it is larger than the sum of its proper divisors (16448801).

81873535 is a wasteful number, since it uses less digits than its factorization.

81873535 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12353.

The product of its digits is 100800, while the sum is 40.

The square root of 81873535 is about 9048.3995822466. The cubic root of 81873535 is about 434.2246902254.

The spelling of 81873535 in words is "eighty-one million, eight hundred seventy-three thousand, five hundred thirty-five".