18009929880 has 256 divisors, whose sum is σ = 65616998400. Its totient is φ = 4374190080.

The previous prime is 18009929879. The next prime is 18009929887. The reversal of 18009929880 is 8892990081.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18009929887) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 553339 + ... + 584981.

It is an arithmetic number, because the mean of its divisors is an integer number (256316400).

Almost surely, 2^18009929880 is an apocalyptic number.

18009929880 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 18009929880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32808499200).

18009929880 is an abundant number, since it is smaller than the sum of its proper divisors (47607068520).

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

18009929880 is a wasteful number, since it uses less digits than its factorization.

18009929880 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31711 (or 31701 counting only the distinct ones).

The product of its (nonzero) digits is 746496, while the sum is 54.

The spelling of 18009929880 in words is "eighteen billion, nine million, nine hundred twenty-nine thousand, eight hundred eighty".