646982161 has 8 divisors (see below), whose sum is σ = 739667264. Its totient is φ = 554361840.

The previous prime is 646982159. The next prime is 646982177. The reversal of 646982161 is 161289646.

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

It is a cyclic number.

It is not a de Polignac number, because 646982161 - 2¹ = 646982159 is a prime.

It is not an unprimeable number, because it can be changed into a prime (646982561) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7531 + ... + 36751.

It is an arithmetic number, because the mean of its divisors is an integer number (92458408).

Almost surely, 2^646982161 is an apocalyptic number.

It is an amenable number.

646982161 is a deficient number, since it is larger than the sum of its proper divisors (92685103).

646982161 is a wasteful number, since it uses less digits than its factorization.

646982161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32391.

The product of its digits is 124416, while the sum is 43.

The square root of 646982161 is about 25435.8440198080. The cubic root of 646982161 is about 864.8964251674.

The spelling of 646982161 in words is "six hundred forty-six million, nine hundred eighty-two thousand, one hundred sixty-one".