18742216 has 8 divisors (see below), whose sum is σ = 35141670. Its totient is φ = 9371104.

The previous prime is 18742201. The next prime is 18742219. The reversal of 18742216 is 61224781.

It can be written as a sum of positive squares in only one way, i.e., 11930116 + 6812100 = 3454^2 + 2610^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is not an unprimeable number, because it can be changed into a prime (18742219) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1171381 + ... + 1171396.

Almost surely, 2^18742216 is an apocalyptic number.

It is an amenable number.

18742216 is a deficient number, since it is larger than the sum of its proper divisors (16399454).

18742216 is a wasteful number, since it uses less digits than its factorization.

18742216 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2342783 (or 2342779 counting only the distinct ones).

The product of its digits is 5376, while the sum is 31.

The square root of 18742216 is about 4329.2281067183. The cubic root of 18742216 is about 265.6278739435.

Adding to 18742216 its reverse (61224781), we get a palindrome (79966997).

The spelling of 18742216 in words is "eighteen million, seven hundred forty-two thousand, two hundred sixteen".