81498605 has 16 divisors (see below), whose sum is σ = 100745904. Its totient is φ = 63244800.

The previous prime is 81498563. The next prime is 81498607. The reversal of 81498605 is 50689418.

It can be written as a sum of positive squares in 8 ways, for example, as 30846916 + 50651689 = 5554^2 + 7117^2 .

It is not a de Polignac number, because 81498605 - 2¹² = 81494509 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81498607) 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, 110819 + ... + 111551.

It is an arithmetic number, because the mean of its divisors is an integer number (6296619).

Almost surely, 2^81498605 is an apocalyptic number.

It is an amenable number.

81498605 is a deficient number, since it is larger than the sum of its proper divisors (19247299).

81498605 is a wasteful number, since it uses less digits than its factorization.

81498605 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1376.

The product of its (nonzero) digits is 69120, while the sum is 41.

The square root of 81498605 is about 9027.6577803991. The cubic root of 81498605 is about 433.5608492954.

The spelling of 81498605 in words is "eighty-one million, four hundred ninety-eight thousand, six hundred five".