78218192 has 20 divisors (see below), whose sum is σ = 163205700. Its totient is φ = 36100608.

The previous prime is 78218159. The next prime is 78218197. The reversal of 78218192 is 29181287.

It can be written as a sum of positive squares in 2 ways, for example, as 15555136 + 62663056 = 3944^2 + 7916^2 .

It is a super-2 number, since 2×78218192² = 12236171119497728, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78218197) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 187817 + ... + 188232.

It is an arithmetic number, because the mean of its divisors is an integer number (8160285).

Almost surely, 2^78218192 is an apocalyptic number.

It is an amenable number.

78218192 is an abundant number, since it is smaller than the sum of its proper divisors (84987508).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

78218192 is a wasteful number, since it uses less digits than its factorization.

78218192 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 376070 (or 376064 counting only the distinct ones).

The product of its digits is 16128, while the sum is 38.

The square root of 78218192 is about 8844.1049292735. The cubic root of 78218192 is about 427.6638989437.

The spelling of 78218192 in words is "seventy-eight million, two hundred eighteen thousand, one hundred ninety-two".