18036473238 has 144 divisors (see below), whose sum is σ = 48550993920. Its totient is φ = 4736938752.

The previous prime is 18036473219. The next prime is 18036473249. The reversal of 18036473238 is 83237463081.

It is a junction number, because it is equal to n+sod(n) for n = 18036473193 and 18036473202.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 1560043 + ... + 1571561.

It is an arithmetic number, because the mean of its divisors is an integer number (337159680).

Almost surely, 2^18036473238 is an apocalyptic number.

18036473238 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 18036473238, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24275496960).

18036473238 is an abundant number, since it is smaller than the sum of its proper divisors (30514520682).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18036473238 is a wasteful number, since it uses less digits than its factorization.

18036473238 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11611 (or 11591 counting only the distinct ones).

The product of its (nonzero) digits is 580608, while the sum is 45.

The spelling of 18036473238 in words is "eighteen billion, thirty-six million, four hundred seventy-three thousand, two hundred thirty-eight".