18160721280 has 384 divisors, whose sum is σ = 67852905120. Its totient is φ = 4449337344.

The previous prime is 18160721279. The next prime is 18160721281. The reversal of 18160721280 is 8212706181.

18160721280 is a `hidden beast` number, since 1 + 8 + 1 + 607 + 21 + 28 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (18160721279) and next prime (18160721281).

It is a tau number, because it is divible by the number of its divisors (384).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18160721281) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 21190612 + ... + 21191468.

Almost surely, 2^18160721280 is an apocalyptic number.

18160721280 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 18160721280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33926452560).

18160721280 is an abundant number, since it is smaller than the sum of its proper divisors (49692183840).

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

18160721280 is a wasteful number, since it uses less digits than its factorization.

18160721280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1178 (or 1163 counting only the distinct ones).

The product of its (nonzero) digits is 10752, while the sum is 36.

The spelling of 18160721280 in words is "eighteen billion, one hundred sixty million, seven hundred twenty-one thousand, two hundred eighty".