78421118 has 4 divisors (see below), whose sum is σ = 117631680. Its totient is φ = 39210558.

The previous prime is 78421117. The next prime is 78421127. The reversal of 78421118 is 81112487.

It is a semiprime because it is the product of two primes.

It is a super-2 number, since 2×78421118² = 12299743496739848, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78421117) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 19605278 + ... + 19605281.

It is an arithmetic number, because the mean of its divisors is an integer number (29407920).

Almost surely, 2^78421118 is an apocalyptic number.

78421118 is a deficient number, since it is larger than the sum of its proper divisors (39210562).

78421118 is a wasteful number, since it uses less digits than its factorization.

78421118 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39210561.

The product of its digits is 3584, while the sum is 32.

The square root of 78421118 is about 8855.5698856708. The cubic root of 78421118 is about 428.0334173401.

The spelling of 78421118 in words is "seventy-eight million, four hundred twenty-one thousand, one hundred eighteen".