161894177280 has 640 divisors, whose sum is σ = 636387840000. Its totient is φ = 38681395200.

The previous prime is 161894177267. The next prime is 161894177293. The reversal of 161894177280 is 82771498161.

161894177280 is a `hidden beast` number, since 1 + 6 + 1 + 89 + 417 + 72 + 80 = 666.

It is an interprime number because it is at equal distance from previous prime (161894177267) and next prime (161894177293).

It is a tau number, because it is divible by the number of its divisors (640).

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

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, 53981221 + ... + 53984219.

It is an arithmetic number, because the mean of its divisors is an integer number (994356000).

Almost surely, 2^161894177280 is an apocalyptic number.

161894177280 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 161894177280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (318193920000).

161894177280 is an abundant number, since it is smaller than the sum of its proper divisors (474493662720).

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

161894177280 is a wasteful number, since it uses less digits than its factorization.

161894177280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3113 (or 3091 counting only the distinct ones).

The product of its (nonzero) digits is 1354752, while the sum is 54.

The spelling of 161894177280 in words is "one hundred sixty-one billion, eight hundred ninety-four million, one hundred seventy-seven thousand, two hundred eighty".