161784656 has 20 divisors (see below), whose sum is σ = 341954304. Its totient is φ = 73538400.

The previous prime is 161784617. The next prime is 161784659. The reversal of 161784656 is 656487161.

It is a Harshad number since it is a multiple of its sum of digits (44).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161784659) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 459440 + ... + 459791.

Almost surely, 2^161784656 is an apocalyptic number.

161784656 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

161784656 is an abundant number, since it is smaller than the sum of its proper divisors (180169648).

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

161784656 is a wasteful number, since it uses less digits than its factorization.

161784656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 919250 (or 919244 counting only the distinct ones).

The product of its digits is 241920, while the sum is 44.

The square root of 161784656 is about 12719.4597369542. The cubic root of 161784656 is about 544.8945238183.

The spelling of 161784656 in words is "one hundred sixty-one million, seven hundred eighty-four thousand, six hundred fifty-six".