18987516240 has 640 divisors, whose sum is σ = 81817620480. Its totient is φ = 3516825600.

The previous prime is 18987516239. The next prime is 18987516241. The reversal of 18987516240 is 4261578981.

It is an interprime number because it is at equal distance from previous prime (18987516239) and next prime (18987516241).

It is a Harshad number since it is a multiple of its sum of digits (51).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18987516241) by changing a digit.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 5967450 + ... + 5970630.

It is an arithmetic number, because the mean of its divisors is an integer number (127840032).

Almost surely, 2^18987516240 is an apocalyptic number.

18987516240 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 18987516240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40908810240).

18987516240 is an abundant number, since it is smaller than the sum of its proper divisors (62830104240).

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

18987516240 is a wasteful number, since it uses less digits than its factorization.

18987516240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3251 (or 3245 counting only the distinct ones).

The product of its (nonzero) digits is 967680, while the sum is 51.

The spelling of 18987516240 in words is "eighteen billion, nine hundred eighty-seven million, five hundred sixteen thousand, two hundred forty".