161681268 has 48 divisors (see below), whose sum is σ = 442811264. Its totient is φ = 44945280.

The previous prime is 161681257. The next prime is 161681291. The reversal of 161681268 is 862186161.

161681268 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×161681268² = 52281664844175648, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 22903 + ... + 29118.

Almost surely, 2^161681268 is an apocalyptic number.

It is an amenable number.

161681268 is an abundant number, since it is smaller than the sum of its proper divisors (281129996).

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

161681268 is a wasteful number, since it uses less digits than its factorization.

161681268 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 52072 (or 52070 counting only the distinct ones).

The product of its digits is 27648, while the sum is 39.

The square root of 161681268 is about 12715.3949211183. The cubic root of 161681268 is about 544.7784280133.

The spelling of 161681268 in words is "one hundred sixty-one million, six hundred eighty-one thousand, two hundred sixty-eight".