18402003 has 12 divisors (see below), whose sum is σ = 27438528. Its totient is φ = 11872080.

The previous prime is 18401983. The next prime is 18402011. The reversal of 18402003 is 30020481.

It is a happy number.

It is not a de Polignac number, because 18402003 - 2¹⁶ = 18336467 is a prime.

It is not an unprimeable number, because it can be changed into a prime (18402073) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 32700 + ... + 33257.

It is an arithmetic number, because the mean of its divisors is an integer number (2286544).

Almost surely, 2^18402003 is an apocalyptic number.

18402003 is a deficient number, since it is larger than the sum of its proper divisors (9036525).

18402003 is a wasteful number, since it uses less digits than its factorization.

18402003 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 65994 (or 65991 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 18.

The square root of 18402003 is about 4289.7555874432. The cubic root of 18402003 is about 264.0108036212.

Adding to 18402003 its reverse (30020481), we get a palindrome (48422484).

The spelling of 18402003 in words is "eighteen million, four hundred two thousand, three".