3651221563 has 16 divisors (see below), whose sum is σ = 4223232000. Its totient is φ = 3119760000.

The previous prime is 3651221557. The next prime is 3651221579.

3651221563 is nontrivially palindromic in base 10.

3651221563 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a cyclic number.

It is not a de Polignac number, because 3651221563 - 2¹⁷ = 3651090491 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (3651221263) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 127438 + ... + 153436.

It is an arithmetic number, because the mean of its divisors is an integer number (263952000).

Almost surely, 2^3651221563 is an apocalyptic number.

3651221563 is a deficient number, since it is larger than the sum of its proper divisors (572010437).

3651221563 is a wasteful number, since it uses less digits than its factorization.

3651221563 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26778.

The product of its digits is 32400, while the sum is 34.

The square root of 3651221563 is about 60425.3387495676. The cubic root of 3651221563 is about 1539.8534693605.

The spelling of 3651221563 in words is "three billion, six hundred fifty-one million, two hundred twenty-one thousand, five hundred sixty-three".