18718772 has 6 divisors (see below), whose sum is σ = 32757858. Its totient is φ = 9359384.

The previous prime is 18718771. The next prime is 18718787. The reversal of 18718772 is 27781781.

It can be written as a sum of positive squares in only one way, i.e., 12348196 + 6370576 = 3514^2 + 2524^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18718771) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2339843 + ... + 2339850.

It is an arithmetic number, because the mean of its divisors is an integer number (5459643).

Almost surely, 2^18718772 is an apocalyptic number.

It is an amenable number.

18718772 is a deficient number, since it is larger than the sum of its proper divisors (14039086).

18718772 is a wasteful number, since it uses less digits than its factorization.

18718772 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4679697 (or 4679695 counting only the distinct ones).

The product of its digits is 43904, while the sum is 41.

The square root of 18718772 is about 4326.5196174292. The cubic root of 18718772 is about 265.5170727764.

The spelling of 18718772 in words is "eighteen million, seven hundred eighteen thousand, seven hundred seventy-two".