18372220416 has 800 divisors, whose sum is σ = 66735871488. Its totient is φ = 4963368960.

The previous prime is 18372220397. The next prime is 18372220507. The reversal of 18372220416 is 61402227381.

It is a happy number.

18372220416 is a `hidden beast` number, since 18 + 3 + 7 + 2 + 220 + 416 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 178371021 + ... + 178371123.

Almost surely, 2^18372220416 is an apocalyptic number.

18372220416 is a gapful number since it is divisible by the number (16) 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 18372220416, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33367935744).

18372220416 is an abundant number, since it is smaller than the sum of its proper divisors (48363651072).

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

18372220416 is a wasteful number, since it uses less digits than its factorization.

18372220416 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 184 (or 159 counting only the distinct ones).

The product of its (nonzero) digits is 32256, while the sum is 36.

Adding to 18372220416 its reverse (61402227381), we get a palindrome (79774447797).

The spelling of 18372220416 in words is "eighteen billion, three hundred seventy-two million, two hundred twenty thousand, four hundred sixteen".