161671786 has 8 divisors (see below), whose sum is σ = 245829924. Its totient is φ = 79728480.

The previous prime is 161671771. The next prime is 161671813. The reversal of 161671786 is 687176161.

161671786 = T₂₀₆₈ + T₂₀₆₉ + ... + T₂₁₄₀.

161671786 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 145950561 + 15721225 = 12081^2 + 3965^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×161671786² = 52275532776859592, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 553525 + ... + 553816.

Almost surely, 2^161671786 is an apocalyptic number.

161671786 is a deficient number, since it is larger than the sum of its proper divisors (84158138).

161671786 is a wasteful number, since it uses less digits than its factorization.

161671786 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1107416.

The product of its digits is 84672, while the sum is 43.

The square root of 161671786 is about 12715.0220605393. The cubic root of 161671786 is about 544.7677780679.

The spelling of 161671786 in words is "one hundred sixty-one million, six hundred seventy-one thousand, seven hundred eighty-six".