161945784 has 384 divisors, whose sum is σ = 620524800. Its totient is φ = 38465280.

The previous prime is 161945743. The next prime is 161945803. The reversal of 161945784 is 487549161.

Its product of digits (241920) is a multiple of the sum of its prime factors (160).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 1513459 + ... + 1513565.

It is an arithmetic number, because the mean of its divisors is an integer number (1615950).

Almost surely, 2^161945784 is an apocalyptic number.

161945784 is a gapful number since it is divisible by the number (14) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 161945784, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (310262400).

161945784 is an abundant number, since it is smaller than the sum of its proper divisors (458579016).

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

161945784 is a wasteful number, since it uses less digits than its factorization.

161945784 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 160 (or 143 counting only the distinct ones).

The product of its digits is 241920, while the sum is 45.

The square root of 161945784 is about 12725.7920775094. The cubic root of 161945784 is about 545.0753580952.

The spelling of 161945784 in words is "one hundred sixty-one million, nine hundred forty-five thousand, seven hundred eighty-four".