18936867840 has 528 divisors, whose sum is σ = 69626559744. Its totient is φ = 4381245440.

The previous prime is 18936867827. The next prime is 18936867853. The reversal of 18936867840 is 4876863981.

It is an interprime number because it is at equal distance from previous prime (18936867827) and next prime (18936867853).

It is a tau number, because it is divible by the number of its divisors (528).

It is a Harshad number since it is a multiple of its sum of digits (60).

It is an unprimeable number.

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 47 ways as a sum of consecutive naturals, for example, 42746659 + ... + 42747101.

Almost surely, 2^18936867840 is an apocalyptic number.

18936867840 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 18936867840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34813279872).

18936867840 is an abundant number, since it is smaller than the sum of its proper divisors (50689691904).

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

18936867840 is a wasteful number, since it uses less digits than its factorization.

18936867840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 516 (or 487 counting only the distinct ones).

The product of its (nonzero) digits is 13934592, while the sum is 60.

The spelling of 18936867840 in words is "eighteen billion, nine hundred thirty-six million, eight hundred sixty-seven thousand, eight hundred forty".