78166449 has 6 divisors (see below), whose sum is σ = 112907106. Its totient is φ = 52110960.

The previous prime is 78166441. The next prime is 78166453. The reversal of 78166449 is 94466187.

It can be written as a sum of positive squares in only one way, i.e., 67765824 + 10400625 = 8232^2 + 3225^2 .

It is not a de Polignac number, because 78166449 - 2³ = 78166441 is a prime.

It is a super-2 number, since 2×78166449² = 12219987498539202, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (78166441) 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 in 5 ways as a sum of consecutive naturals, for example, 4342572 + ... + 4342589.

It is an arithmetic number, because the mean of its divisors is an integer number (18817851).

Almost surely, 2^78166449 is an apocalyptic number.

It is an amenable number.

78166449 is a deficient number, since it is larger than the sum of its proper divisors (34740657).

78166449 is a wasteful number, since it uses less digits than its factorization.

78166449 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8685167 (or 8685164 counting only the distinct ones).

The product of its digits is 290304, while the sum is 45.

The square root of 78166449 is about 8841.1791634374. The cubic root of 78166449 is about 427.5695752155.

The spelling of 78166449 in words is "seventy-eight million, one hundred sixty-six thousand, four hundred forty-nine".