18203974605 has 18 divisors (see below), whose sum is σ = 31555124874. Its totient is φ = 9708303744.

The previous prime is 18203974583. The next prime is 18203974609. The reversal of 18203974605 is 50647930281.

18203974605 is a `hidden beast` number, since 1 + 8 + 2 + 0 + 39 + 7 + 4 + 605 = 666.

It can be written as a sum of positive squares in 3 ways, for example, as 818760996 + 17385213609 = 28614^2 + 131853^2 .

It is not a de Polignac number, because 18203974605 - 2²² = 18199780301 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18203974609) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 895029 + ... + 915141.

It is an arithmetic number, because the mean of its divisors is an integer number (1753062493).

It is a 1-persistent number, because it is pandigital, but 2⋅18203974605 = 36407949210 is not.

Almost surely, 2^18203974605 is an apocalyptic number.

18203974605 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

18203974605 is a deficient number, since it is larger than the sum of its proper divisors (13351150269).

18203974605 is an frugal number, since it uses more digits than its factorization.

18203974605 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40237 (or 20121 counting only the distinct ones).

The product of its (nonzero) digits is 362880, while the sum is 45.

Multiplying 18203974605 by its sum of digits (45), we get a square (819178857225 = 905085²).

18203974605 divided by its sum of digits (45) gives a square (404532769 = 20113²).

The spelling of 18203974605 in words is "eighteen billion, two hundred three million, nine hundred seventy-four thousand, six hundred five".