81480197 has 4 divisors (see below), whose sum is σ = 81722316. Its totient is φ = 81238080.

The previous prime is 81480193. The next prime is 81480209. The reversal of 81480197 is 79108418.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 79108418 = 2 ⋅39554209.

It can be written as a sum of positive squares in 2 ways, for example, as 55815841 + 25664356 = 7471^2 + 5066^2 .

It is a cyclic number.

It is not a de Polignac number, because 81480197 - 2² = 81480193 is a prime.

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 81480197.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81480193) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 120554 + ... + 121227.

It is an arithmetic number, because the mean of its divisors is an integer number (20430579).

Almost surely, 2^81480197 is an apocalyptic number.

It is an amenable number.

81480197 is a deficient number, since it is larger than the sum of its proper divisors (242119).

81480197 is a wasteful number, since it uses less digits than its factorization.

81480197 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 242118.

The product of its (nonzero) digits is 16128, while the sum is 38.

The square root of 81480197 is about 9026.6381892707. The cubic root of 81480197 is about 433.5282042005.

The spelling of 81480197 in words is "eighty-one million, four hundred eighty thousand, one hundred ninety-seven".