161780340 has 48 divisors (see below), whose sum is σ = 455317632. Its totient is φ = 42919296.

The previous prime is 161780309. The next prime is 161780341. The reversal of 161780340 is 43087161.

It is a happy number.

161780340 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

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 = 161780298 and 161780307.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161780341) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4977 + ... + 18663.

It is an arithmetic number, because the mean of its divisors is an integer number (9485784).

Almost surely, 2^161780340 is an apocalyptic number.

161780340 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

161780340 is an abundant number, since it is smaller than the sum of its proper divisors (293537292).

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

161780340 is a wasteful number, since it uses less digits than its factorization.

161780340 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13896 (or 13894 counting only the distinct ones).

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

The square root of 161780340 is about 12719.2900745285. The cubic root of 161780340 is about 544.8896783121.

The spelling of 161780340 in words is "one hundred sixty-one million, seven hundred eighty thousand, three hundred forty".