161997396 has 96 divisors (see below), whose sum is σ = 434367360. Its totient is φ = 46540800.

The previous prime is 161997379. The next prime is 161997397. The reversal of 161997396 is 693799161.

161997396 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161997397) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 199840 + ... + 200648.

It is an arithmetic number, because the mean of its divisors is an integer number (4524660).

Almost surely, 2^161997396 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 161997396, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (217183680).

161997396 is an abundant number, since it is smaller than the sum of its proper divisors (272369964).

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

161997396 is a wasteful number, since it uses less digits than its factorization.

161997396 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 905 (or 903 counting only the distinct ones).

The product of its digits is 551124, while the sum is 51.

The square root of 161997396 is about 12727.8197661658. The cubic root of 161997396 is about 545.1332569809.

The spelling of 161997396 in words is "one hundred sixty-one million, nine hundred ninety-seven thousand, three hundred ninety-six".