81580797 has 16 divisors (see below), whose sum is σ = 121204480. Its totient is φ = 54232416.

The previous prime is 81580787. The next prime is 81580801. The reversal of 81580797 is 79708518.

It is not a de Polignac number, because 81580797 - 2¹⁶ = 81515261 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 (81580717) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5793 + ... + 14025.

It is an arithmetic number, because the mean of its divisors is an integer number (7575280).

Almost surely, 2^81580797 is an apocalyptic number.

It is an amenable number.

81580797 is a deficient number, since it is larger than the sum of its proper divisors (39623683).

81580797 is a wasteful number, since it uses less digits than its factorization.

81580797 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8609 (or 8603 counting only the distinct ones).

The product of its (nonzero) digits is 141120, while the sum is 45.

The square root of 81580797 is about 9032.2088660526. The cubic root of 81580797 is about 433.7065501965.

The spelling of 81580797 in words is "eighty-one million, five hundred eighty thousand, seven hundred ninety-seven".