1816363640 has 256 divisors, whose sum is σ = 5388768000. Its totient is φ = 534675456.

The previous prime is 1816363607. The next prime is 1816363649. The reversal of 1816363640 is 463636181.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 1816363594 and 1816363603.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1816363649) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 9220022 + ... + 9220218.

It is an arithmetic number, because the mean of its divisors is an integer number (21049875).

Almost surely, 2^1816363640 is an apocalyptic number.

1816363640 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 1816363640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2694384000).

1816363640 is an abundant number, since it is smaller than the sum of its proper divisors (3572404360).

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

1816363640 is a wasteful number, since it uses less digits than its factorization.

1816363640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 394 (or 390 counting only the distinct ones).

The product of its (nonzero) digits is 62208, while the sum is 38.

The square root of 1816363640 is about 42618.8179094634. The cubic root of 1816363640 is about 1220.1154687807.

The spelling of 1816363640 in words is "one billion, eight hundred sixteen million, three hundred sixty-three thousand, six hundred forty".