18236321940 has 288 divisors, whose sum is σ = 56303662464. Its totient is φ = 4406312960.

The previous prime is 18236321933. The next prime is 18236321953. The reversal of 18236321940 is 4912363281.

It is a hoax number, since the sum of its digits (39) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 80336107 + ... + 80336333.

It is an arithmetic number, because the mean of its divisors is an integer number (195498828).

Almost surely, 2^18236321940 is an apocalyptic number.

18236321940 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18236321940, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28151831232).

18236321940 is an abundant number, since it is smaller than the sum of its proper divisors (38067340524).

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

18236321940 is a wasteful number, since it uses less digits than its factorization.

18236321940 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 427 (or 408 counting only the distinct ones).

The product of its (nonzero) digits is 62208, while the sum is 39.

The spelling of 18236321940 in words is "eighteen billion, two hundred thirty-six million, three hundred twenty-one thousand, nine hundred forty".