4381563661 has 2 divisors, whose sum is σ = 4381563662. Its totient is φ = 4381563660.

The previous prime is 4381563617. The next prime is 4381563701. The reversal of 4381563661 is 1663651834.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 4381116100 + 447561 = 66190^2 + 669^2 .

It is a cyclic number.

It is not a de Polignac number, because 4381563661 - 2¹⁹ = 4381039373 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (4381563601) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2190781830 + 2190781831.

It is an arithmetic number, because the mean of its divisors is an integer number (2190781831).

Almost surely, 2^4381563661 is an apocalyptic number.

It is an amenable number.

4381563661 is a deficient number, since it is larger than the sum of its proper divisors (1).

4381563661 is an equidigital number, since it uses as much as digits as its factorization.

4381563661 is an evil number, because the sum of its binary digits is even.

The product of its digits is 311040, while the sum is 43.

The square root of 4381563661 is about 66193.3807944571. The cubic root of 4381563661 is about 1636.3506576590.

The spelling of 4381563661 in words is "four billion, three hundred eighty-one million, five hundred sixty-three thousand, six hundred sixty-one".