78222871 has 2 divisors, whose sum is σ = 78222872. Its totient is φ = 78222870.

The previous prime is 78222863. The next prime is 78222883. The reversal of 78222871 is 17822287.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 78222871 - 2³ = 78222863 is a prime.

It is a super-2 number, since 2×78222871² = 12237635094965282, which contains 22 as substring.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 78222871.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78222841) 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, 39111435 + 39111436.

It is an arithmetic number, because the mean of its divisors is an integer number (39111436).

Almost surely, 2^78222871 is an apocalyptic number.

78222871 is a deficient number, since it is larger than the sum of its proper divisors (1).

78222871 is an equidigital number, since it uses as much as digits as its factorization.

78222871 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 25088, while the sum is 37.

The square root of 78222871 is about 8844.3694518038. The cubic root of 78222871 is about 427.6724263695.

It can be divided in two parts, 782 and 22871, that added together give a triangular number (23653 = T₂₁₇).

The spelling of 78222871 in words is "seventy-eight million, two hundred twenty-two thousand, eight hundred seventy-one".