18438177516 has 48 divisors (see below), whose sum is σ = 48974139648. Its totient is φ = 5344398400.

The previous prime is 18438177481. The next prime is 18438177517. The reversal of 18438177516 is 61577183481.

It is a super-2 number, since 2×18438177516² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (18438177517) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3033555 + ... + 3039626.

It is an arithmetic number, because the mean of its divisors is an integer number (1020294576).

Almost surely, 2^18438177516 is an apocalyptic number.

It is an amenable number.

18438177516 is an abundant number, since it is smaller than the sum of its proper divisors (30535962132).

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

18438177516 is a wasteful number, since it uses less digits than its factorization.

18438177516 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6073222 (or 6073220 counting only the distinct ones).

The product of its digits is 1128960, while the sum is 51.

The spelling of 18438177516 in words is "eighteen billion, four hundred thirty-eight million, one hundred seventy-seven thousand, five hundred sixteen".