78281573 has 2 divisors, whose sum is σ = 78281574. Its totient is φ = 78281572.

The previous prime is 78281557. The next prime is 78281579. The reversal of 78281573 is 37518287.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 40360609 + 37920964 = 6353^2 + 6158^2 .

It is an emirp because it is prime and its reverse (37518287) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 78281573 - 2⁴ = 78281557 is a prime.

It is a super-2 number, since 2×78281573² = 12256009342708658, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 78281573.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78281579) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39140786 + 39140787.

It is an arithmetic number, because the mean of its divisors is an integer number (39140787).

Almost surely, 2^78281573 is an apocalyptic number.

It is an amenable number.

78281573 is a deficient number, since it is larger than the sum of its proper divisors (1).

78281573 is an equidigital number, since it uses as much as digits as its factorization.

78281573 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 94080, while the sum is 41.

The square root of 78281573 is about 8847.6874379693. The cubic root of 78281573 is about 427.7793812325.

The spelling of 78281573 in words is "seventy-eight million, two hundred eighty-one thousand, five hundred seventy-three".