646118153 has 4 divisors (see below), whose sum is σ = 646175508. Its totient is φ = 646060800.

The previous prime is 646118147. The next prime is 646118183. The reversal of 646118153 is 351811646.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 351811646 = 2 ⋅175905823.

It can be written as a sum of positive squares in 2 ways, for example, as 494261824 + 151856329 = 22232^2 + 12323^2 .

It is a cyclic number.

It is not a de Polignac number, because 646118153 - 2¹⁸ = 645856009 is a prime.

It is a super-2 number, since 2×646118153² = 834937335272262818, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (646118113) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5576 + ... + 36377.

It is an arithmetic number, because the mean of its divisors is an integer number (161543877).

Almost surely, 2^646118153 is an apocalyptic number.

It is an amenable number.

646118153 is a deficient number, since it is larger than the sum of its proper divisors (57355).

646118153 is a wasteful number, since it uses less digits than its factorization.

646118153 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 57354.

The product of its digits is 17280, while the sum is 35.

The square root of 646118153 is about 25418.8542818122. The cubic root of 646118153 is about 864.5112469397.

Adding to 646118153 its reverse (351811646), we get a palindrome (997929799).

The spelling of 646118153 in words is "six hundred forty-six million, one hundred eighteen thousand, one hundred fifty-three".