161945040 has 40 divisors (see below), whose sum is σ = 502030368. Its totient is φ = 43185280.

The previous prime is 161945027. The next prime is 161945071. The reversal of 161945040 is 40549161.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (40).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 161944989 and 161945007.

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 7 ways as a sum of consecutive naturals, for example, 337146 + ... + 337625.

Almost surely, 2^161945040 is an apocalyptic number.

161945040 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

161945040 is an abundant number, since it is smaller than the sum of its proper divisors (340085328).

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

161945040 is a wasteful number, since it uses less digits than its factorization.

161945040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 674787 (or 674781 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 30.

The square root of 161945040 is about 12725.7628455036. The cubic root of 161945040 is about 545.0745233782.

The spelling of 161945040 in words is "one hundred sixty-one million, nine hundred forty-five thousand, forty".