78166705 has 8 divisors (see below), whose sum is σ = 96088104. Its totient is φ = 61008000.

The previous prime is 78166691. The next prime is 78166723. The reversal of 78166705 is 50766187.

It can be written as a sum of positive squares in 4 ways, for example, as 2702736 + 75463969 = 1644^2 + 8687^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 78166705 - 2¹³ = 78158513 is a prime.

It is a super-2 number, since 2×78166705² = 12220067541114050, which contains 22 as substring.

It is a Duffinian number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 190446 + ... + 190855.

It is an arithmetic number, because the mean of its divisors is an integer number (12011013).

Almost surely, 2^78166705 is an apocalyptic number.

It is an amenable number.

78166705 is a deficient number, since it is larger than the sum of its proper divisors (17921399).

78166705 is a wasteful number, since it uses less digits than its factorization.

78166705 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 381347.

The product of its (nonzero) digits is 70560, while the sum is 40.

The square root of 78166705 is about 8841.1936411324. The cubic root of 78166705 is about 427.5700419874.

The spelling of 78166705 in words is "seventy-eight million, one hundred sixty-six thousand, seven hundred five".