161680878 has 24 divisors (see below), whose sum is σ = 350693928. Its totient is φ = 53834352.

The previous prime is 161680873. The next prime is 161680889. The reversal of 161680878 is 878086161.

It is a super-2 number, since 2×161680878² = 52281412621701768, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161680873) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 13801 + ... + 22667.

It is an arithmetic number, because the mean of its divisors is an integer number (14612247).

Almost surely, 2^161680878 is an apocalyptic number.

161680878 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

161680878 is an abundant number, since it is smaller than the sum of its proper divisors (189013050).

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

161680878 is a wasteful number, since it uses less digits than its factorization.

161680878 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9888 (or 9885 counting only the distinct ones).

The product of its (nonzero) digits is 129024, while the sum is 45.

The square root of 161680878 is about 12715.3795853683. The cubic root of 161680878 is about 544.7779899833. Note that the first 3 decimals are identical.

The spelling of 161680878 in words is "one hundred sixty-one million, six hundred eighty thousand, eight hundred seventy-eight".