4639857561 has 24 divisors (see below), whose sum is σ = 6739046600. Its totient is φ = 3076185600.

The previous prime is 4639857557. The next prime is 4639857569. The reversal of 4639857561 is 1657589364.

4639857561 is a `hidden beast` number, since 4 + 6 + 3 + 9 + 8 + 575 + 61 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 770395536 + 3869462025 = 27756^2 + 62205^2 .

It is not a de Polignac number, because 4639857561 - 2² = 4639857557 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 4639857498 and 4639857507.

It is not an unprimeable number, because it can be changed into a prime (4639857569) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2994615 + ... + 2996163.

Almost surely, 2^4639857561 is an apocalyptic number.

It is an amenable number.

4639857561 is a deficient number, since it is larger than the sum of its proper divisors (2099189039).

4639857561 is a wasteful number, since it uses less digits than its factorization.

4639857561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3177 (or 3174 counting only the distinct ones).

The product of its digits is 5443200, while the sum is 54.

The square root of 4639857561 is about 68116.4999174209. The cubic root of 4639857561 is about 1667.8931157034.

The spelling of 4639857561 in words is "four billion, six hundred thirty-nine million, eight hundred fifty-seven thousand, five hundred sixty-one".