81580801 has 2 divisors, whose sum is σ = 81580802. Its totient is φ = 81580800.

The previous prime is 81580787. The next prime is 81580823. The reversal of 81580801 is 10808518.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 81432576 + 148225 = 9024^2 + 385^2 .

It is a cyclic number.

It is not a de Polignac number, because 81580801 - 2⁵ = 81580769 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (81580601) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40790400 + 40790401.

It is an arithmetic number, because the mean of its divisors is an integer number (40790401).

Almost surely, 2^81580801 is an apocalyptic number.

It is an amenable number.

81580801 is a deficient number, since it is larger than the sum of its proper divisors (1).

81580801 is an equidigital number, since it uses as much as digits as its factorization.

81580801 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2560, while the sum is 31.

The square root of 81580801 is about 9032.2090874824. The cubic root of 81580801 is about 433.7065572848.

The spelling of 81580801 in words is "eighty-one million, five hundred eighty thousand, eight hundred one".