161978526 has 48 divisors (see below), whose sum is σ = 363967344. Its totient is φ = 52019712.

The previous prime is 161978501. The next prime is 161978527. The reversal of 161978526 is 625879161.

161978526 is a `hidden beast` number, since 1 + 619 + 7 + 8 + 5 + 26 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161978527) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 70126 + ... + 72398.

It is an arithmetic number, because the mean of its divisors is an integer number (7582653).

Almost surely, 2^161978526 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 161978526, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (181983672).

161978526 is an abundant number, since it is smaller than the sum of its proper divisors (201988818).

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

161978526 is a wasteful number, since it uses less digits than its factorization.

161978526 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2425 (or 2422 counting only the distinct ones).

The product of its digits is 181440, while the sum is 45.

The square root of 161978526 is about 12727.0784550108. The cubic root of 161978526 is about 545.1120898423.

The spelling of 161978526 in words is "one hundred sixty-one million, nine hundred seventy-eight thousand, five hundred twenty-six".