3649638581 has 8 divisors (see below), whose sum is σ = 3667644480. Its totient is φ = 3631650048.

The previous prime is 3649638547. The next prime is 3649638599. The reversal of 3649638581 is 1858369463.

3649638581 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-3649638581 is a prime.

It is a super-2 number, since 2×3649638581² = 26639723543847387122, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3649638281) 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, 652565 + ... + 658133.

It is an arithmetic number, because the mean of its divisors is an integer number (458455560).

Almost surely, 2^3649638581 is an apocalyptic number.

It is an amenable number.

3649638581 is a deficient number, since it is larger than the sum of its proper divisors (18005899).

3649638581 is a wasteful number, since it uses less digits than its factorization.

3649638581 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8683.

The product of its digits is 3732480, while the sum is 53.

The square root of 3649638581 is about 60412.2386689982. The cubic root of 3649638581 is about 1539.6309034206.

The spelling of 3649638581 in words is "three billion, six hundred forty-nine million, six hundred thirty-eight thousand, five hundred eighty-one".