78166641 has 8 divisors (see below), whose sum is σ = 119111104. Its totient is φ = 44666640.

The previous prime is 78166639. The next prime is 78166657. The reversal of 78166641 is 14666187.

It is a happy number.

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

It is not a de Polignac number, because 78166641 - 2¹ = 78166639 is a prime.

It is a super-2 number, since 2×78166641² = 12220047530445762, 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 78166641.

It is not an unprimeable number, because it can be changed into a prime (78166601) 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 7 ways as a sum of consecutive naturals, for example, 1861090 + ... + 1861131.

It is an arithmetic number, because the mean of its divisors is an integer number (14888888).

Almost surely, 2^78166641 is an apocalyptic number.

It is an amenable number.

78166641 is a deficient number, since it is larger than the sum of its proper divisors (40944463).

78166641 is a wasteful number, since it uses less digits than its factorization.

78166641 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3722231.

The product of its digits is 48384, while the sum is 39.

The square root of 78166641 is about 8841.1900217109. The cubic root of 78166641 is about 427.5699252945.

The spelling of 78166641 in words is "seventy-eight million, one hundred sixty-six thousand, six hundred forty-one".