161978368 has 48 divisors (see below), whose sum is σ = 326781000. Its totient is φ = 80265216.

The previous prime is 161978359. The next prime is 161978387. The reversal of 161978368 is 863879161.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 284388 + ... + 284956.

Almost surely, 2^161978368 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 161978368, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (163390500).

161978368 is an abundant number, since it is smaller than the sum of its proper divisors (164802632).

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

161978368 is an equidigital number, since it uses as much as digits as its factorization.

161978368 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 730 (or 710 counting only the distinct ones).

The product of its digits is 435456, while the sum is 49.

The square root of 161978368 is about 12727.0722477717. The cubic root of 161978368 is about 545.1119126012. Note that the first 3 decimals are identical.

The spelling of 161978368 in words is "one hundred sixty-one million, nine hundred seventy-eight thousand, three hundred sixty-eight".