161671440 has 80 divisors (see below), whose sum is σ = 572784768. Its totient is φ = 36953088.

The previous prime is 161671409. The next prime is 161671457. The reversal of 161671440 is 44176161.

161671440 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (80).

It is a super-2 number, since 2×161671440² = 52275309023347200, which contains 22 as substring.

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 = 161671398 and 161671407.

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 15 ways as a sum of consecutive naturals, for example, 46437 + ... + 49796.

Almost surely, 2^161671440 is an apocalyptic number.

161671440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

161671440 is an abundant number, since it is smaller than the sum of its proper divisors (411113328).

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

161671440 is a wasteful number, since it uses less digits than its factorization.

161671440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 96256 (or 96250 counting only the distinct ones).

The product of its (nonzero) digits is 4032, while the sum is 30.

The square root of 161671440 is about 12715.0084545784. The cubic root of 161671440 is about 544.7673894415.

The spelling of 161671440 in words is "one hundred sixty-one million, six hundred seventy-one thousand, four hundred forty".