3639120851 has 4 divisors (see below), whose sum is σ = 3639517272. Its totient is φ = 3638724432.

The previous prime is 3639120847. The next prime is 3639120853. The reversal of 3639120851 is 1580219363.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1580219363 = 6367 ⋅248189.

It is a cyclic number.

It is not a de Polignac number, because 3639120851 - 2² = 3639120847 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (3639120853) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 184106 + ... + 202911.

It is an arithmetic number, because the mean of its divisors is an integer number (909879318).

Almost surely, 2^3639120851 is an apocalyptic number.

3639120851 is a deficient number, since it is larger than the sum of its proper divisors (396421).

3639120851 is an equidigital number, since it uses as much as digits as its factorization.

3639120851 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 396420.

The product of its (nonzero) digits is 38880, while the sum is 38.

The square root of 3639120851 is about 60325.1261996193. The cubic root of 3639120851 is about 1538.1504826032.

The spelling of 3639120851 in words is "three billion, six hundred thirty-nine million, one hundred twenty thousand, eight hundred fifty-one".