28203101581 has 2 divisors, whose sum is σ = 28203101582. Its totient is φ = 28203101580.

The previous prime is 28203101501. The next prime is 28203101617. The reversal of 28203101581 is 18510130282.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20623832100 + 7579269481 = 143610^2 + 87059^2 .

It is a cyclic number.

It is not a de Polignac number, because 28203101581 - 2⁷ = 28203101453 is a prime.

It is a super-2 number, since 2×28203101581² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28203101501) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14101550790 + 14101550791.

It is an arithmetic number, because the mean of its divisors is an integer number (14101550791).

Almost surely, 2^28203101581 is an apocalyptic number.

It is an amenable number.

28203101581 is a deficient number, since it is larger than the sum of its proper divisors (1).

28203101581 is an equidigital number, since it uses as much as digits as its factorization.

28203101581 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3840, while the sum is 31.

The spelling of 28203101581 in words is "twenty-eight billion, two hundred three million, one hundred one thousand, five hundred eighty-one".