81605703 has 16 divisors (see below), whose sum is σ = 117331200. Its totient is φ = 50281920.

The previous prime is 81605659. The next prime is 81605707. The reversal of 81605703 is 30750618.

It is not a de Polignac number, because 81605703 - 2¹³ = 81597511 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81605707) 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, 15123 + ... + 19796.

It is an arithmetic number, because the mean of its divisors is an integer number (7333200).

Almost surely, 2^81605703 is an apocalyptic number.

81605703 is a deficient number, since it is larger than the sum of its proper divisors (35725497).

81605703 is a wasteful number, since it uses less digits than its factorization.

81605703 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34982.

The product of its (nonzero) digits is 5040, while the sum is 30.

The square root of 81605703 is about 9033.5874933495. The cubic root of 81605703 is about 433.7506814818.

The spelling of 81605703 in words is "eighty-one million, six hundred five thousand, seven hundred three".