161778032 has 40 divisors (see below), whose sum is σ = 340592784. Its totient is φ = 73995264.

The previous prime is 161778013. The next prime is 161778041. The reversal of 161778032 is 230877161.

It is a junction number, because it is equal to n+sod(n) for n = 161777983 and 161778001.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 20063 + ... + 26945.

Almost surely, 2^161778032 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 161778032, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (170296392).

161778032 is an abundant number, since it is smaller than the sum of its proper divisors (178814752).

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

161778032 is a wasteful number, since it uses less digits than its factorization.

161778032 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7017 (or 7011 counting only the distinct ones).

The product of its (nonzero) digits is 14112, while the sum is 35.

The square root of 161778032 is about 12719.1993458708. The cubic root of 161778032 is about 544.8870871210.

The spelling of 161778032 in words is "one hundred sixty-one million, seven hundred seventy-eight thousand, thirty-two".