81596493801 has 45 divisors (see below), whose sum is σ = 129552279879. Its totient is φ = 51170377536.

The previous prime is 81596493763. The next prime is 81596493809. The reversal of 81596493801 is 10839469518.

The square root of 81596493801 is 285651.

It is a perfect power (a square), and thus also a powerful number.

81596493801 is a `hidden beast` number, since 8 + 1 + 596 + 49 + 3 + 8 + 0 + 1 = 666.

It can be written as a sum of positive squares in only one way, i.e., 63526682025 + 18069811776 = 252045^2 + 134424^2 .

It is not a de Polignac number, because 81596493801 - 2¹⁹ = 81595969513 is a prime.

It is not an unprimeable number, because it can be changed into a prime (81596493809) by changing a digit.

It is a polite number, since it can be written in 44 ways as a sum of consecutive naturals, for example, 43703670 + ... + 43705536.

Almost surely, 2^81596493801 is an apocalyptic number.

81596493801 is a gapful number since it is divisible by the number (81) formed by its first and last digit.

81596493801 is the 285651-st square number.

81596493801 is the 142826-th centered octagonal number.

It is an amenable number.

81596493801 is a deficient number, since it is larger than the sum of its proper divisors (47955786078).

81596493801 is an frugal number, since it uses more digits than its factorization.

81596493801 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3780 (or 1887 counting only the distinct ones).

The product of its (nonzero) digits is 1866240, while the sum is 54.

The spelling of 81596493801 in words is "eighty-one billion, five hundred ninety-six million, four hundred ninety-three thousand, eight hundred one".