78722218 has 8 divisors (see below), whose sum is σ = 118122048. Its totient is φ = 39348204.

The previous prime is 78722197. The next prime is 78722221. The reversal of 78722218 is 81222787.

It is a happy number.

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

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5905 + ... + 13867.

It is an arithmetic number, because the mean of its divisors is an integer number (14765256).

Almost surely, 2^78722218 is an apocalyptic number.

78722218 is a deficient number, since it is larger than the sum of its proper divisors (39399830).

78722218 is a wasteful number, since it uses less digits than its factorization.

78722218 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12908.

The product of its digits is 25088, while the sum is 37.

The square root of 78722218 is about 8872.5541982002. The cubic root of 78722218 is about 428.5805330024.

It can be divided in two parts, 787 and 22218, that added together give a triangular number (23005 = T₂₁₄).

The spelling of 78722218 in words is "seventy-eight million, seven hundred twenty-two thousand, two hundred eighteen".