78832781 has 2 divisors, whose sum is σ = 78832782. Its totient is φ = 78832780.

The previous prime is 78832769. The next prime is 78832807. The reversal of 78832781 is 18723887.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 62267881 + 16564900 = 7891^2 + 4070^2 .

It is a cyclic number.

It is not a de Polignac number, because 78832781 - 2¹⁰ = 78831757 is a prime.

It is a super-2 number, since 2×78832781² = 12429214720387922, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78832181) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39416390 + 39416391.

It is an arithmetic number, because the mean of its divisors is an integer number (39416391).

Almost surely, 2^78832781 is an apocalyptic number.

It is an amenable number.

78832781 is a deficient number, since it is larger than the sum of its proper divisors (1).

78832781 is an equidigital number, since it uses as much as digits as its factorization.

78832781 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 150528, while the sum is 44.

The square root of 78832781 is about 8878.7826305187. The cubic root of 78832781 is about 428.7810819888.

The spelling of 78832781 in words is "seventy-eight million, eight hundred thirty-two thousand, seven hundred eighty-one".