78166441 has 2 divisors, whose sum is σ = 78166442. Its totient is φ = 78166440.

The previous prime is 78166433. The next prime is 78166453. The reversal of 78166441 is 14466187.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 60902416 + 17264025 = 7804^2 + 4155^2 .

It is a cyclic number.

It is not a de Polignac number, because 78166441 - 2³ = 78166433 is a prime.

It is a super-2 number, since 2×78166441² = 12219984997212962, 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 78166441.

It is not a weakly prime, because it can be changed into another prime (78166481) 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, 39083220 + 39083221.

It is an arithmetic number, because the mean of its divisors is an integer number (39083221).

Almost surely, 2^78166441 is an apocalyptic number.

It is an amenable number.

78166441 is a deficient number, since it is larger than the sum of its proper divisors (1).

78166441 is an equidigital number, since it uses as much as digits as its factorization.

78166441 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 32256, while the sum is 37.

The square root of 78166441 is about 8841.1787110091. The cubic root of 78166441 is about 427.5695606289.

The spelling of 78166441 in words is "seventy-eight million, one hundred sixty-six thousand, four hundred forty-one".