646118161 has 36 divisors (see below), whose sum is σ = 766783836. Its totient is φ = 540743040.

The previous prime is 646118147. The next prime is 646118183. The reversal of 646118161 is 161811646.

It is a happy number.

It can be written as a sum of positive squares in 6 ways, for example, as 189227536 + 456890625 = 13756^2 + 21375^2 .

It is not a de Polignac number, because 646118161 - 2²³ = 637729553 is a prime.

It is not an unprimeable number, because it can be changed into a prime (646118111) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 10592071 + ... + 10592131.

It is an arithmetic number, because the mean of its divisors is an integer number (21299551).

Almost surely, 2^646118161 is an apocalyptic number.

646118161 is a gapful number since it is divisible by the number (61) formed by its first and last digit.

It is an amenable number.

646118161 is a deficient number, since it is larger than the sum of its proper divisors (120665675).

646118161 is a wasteful number, since it uses less digits than its factorization.

646118161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 210 (or 130 counting only the distinct ones).

The product of its digits is 6912, while the sum is 34.

The square root of 646118161 is about 25418.8544391757. The cubic root of 646118161 is about 864.5112505077.

The spelling of 646118161 in words is "six hundred forty-six million, one hundred eighteen thousand, one hundred sixty-one".