81280037 has 2 divisors, whose sum is σ = 81280038. Its totient is φ = 81280036.

The previous prime is 81279983. The next prime is 81280049. The reversal of 81280037 is 73008218.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 73805281 + 7474756 = 8591^2 + 2734^2 .

It is a cyclic number.

It is not a de Polignac number, because 81280037 - 2⁶ = 81279973 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 81279991 and 81280009.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81280237) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40640018 + 40640019.

It is an arithmetic number, because the mean of its divisors is an integer number (40640019).

Almost surely, 2^81280037 is an apocalyptic number.

It is an amenable number.

81280037 is a deficient number, since it is larger than the sum of its proper divisors (1).

81280037 is an equidigital number, since it uses as much as digits as its factorization.

81280037 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2688, while the sum is 29.

The square root of 81280037 is about 9015.5441876794. The cubic root of 81280037 is about 433.1729188619.

The spelling of 81280037 in words is "eighty-one million, two hundred eighty thousand, thirty-seven".