18399716 has 6 divisors (see below), whose sum is σ = 32199510. Its totient is φ = 9199856.

The previous prime is 18399713. The next prime is 18399727. The reversal of 18399716 is 61799381.

It can be written as a sum of positive squares in only one way, i.e., 17305600 + 1094116 = 4160^2 + 1046^2 .

It is not an unprimeable number, because it can be changed into a prime (18399713) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2299961 + ... + 2299968.

It is an arithmetic number, because the mean of its divisors is an integer number (5366585).

Almost surely, 2^18399716 is an apocalyptic number.

It is an amenable number.

18399716 is a deficient number, since it is larger than the sum of its proper divisors (13799794).

18399716 is a wasteful number, since it uses less digits than its factorization.

18399716 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4599933 (or 4599931 counting only the distinct ones).

The product of its digits is 81648, while the sum is 44.

The square root of 18399716 is about 4289.4890138570. The cubic root of 18399716 is about 263.9998660850. Note that the first 3 decimals are identical.

It can be divided in two parts, 183 and 99716, that added together give a palindrome (99899).

The spelling of 18399716 in words is "eighteen million, three hundred ninety-nine thousand, seven hundred sixteen".