18487944657120 has 384 divisors, whose sum is σ = 61045510643712. Its totient is φ = 4697467084800.

The previous prime is 18487944657109. The next prime is 18487944657131. The reversal of 18487944657120 is 2175644978481.

It is a Cunningham number, because it is equal to 4299761²-1.

It is an interprime number because it is at equal distance from previous prime (18487944657109) and next prime (18487944657131).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 799743802 + ... + 799766918.

It is an arithmetic number, because the mean of its divisors is an integer number (158972683968).

Almost surely, 2^{18487944657120} is an apocalyptic number.

18487944657120 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 18487944657120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30522755321856).

18487944657120 is an abundant number, since it is smaller than the sum of its proper divisors (42557565986592).

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

18487944657120 is a wasteful number, since it uses less digits than its factorization.

18487944657120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23994 (or 23986 counting only the distinct ones).

The product of its (nonzero) digits is 108380160, while the sum is 66.

The spelling of 18487944657120 in words is "eighteen trillion, four hundred eighty-seven billion, nine hundred forty-four million, six hundred fifty-seven thousand, one hundred twenty".