3642557561 has 2 divisors, whose sum is σ = 3642557562. Its totient is φ = 3642557560.

The previous prime is 3642557551. The next prime is 3642557579. The reversal of 3642557561 is 1657552463.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2763079225 + 879478336 = 52565^2 + 29656^2 .

It is a cyclic number.

It is not a de Polignac number, because 3642557561 - 2¹⁰ = 3642556537 is a prime.

It is not a weakly prime, because it can be changed into another prime (3642557521) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1821278780 + 1821278781.

It is an arithmetic number, because the mean of its divisors is an integer number (1821278781).

Almost surely, 2^3642557561 is an apocalyptic number.

It is an amenable number.

3642557561 is a deficient number, since it is larger than the sum of its proper divisors (1).

3642557561 is an equidigital number, since it uses as much as digits as its factorization.

3642557561 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 756000, while the sum is 44.

The square root of 3642557561 is about 60353.6043745525. The cubic root of 3642557561 is about 1538.6345293627.

The spelling of 3642557561 in words is "three billion, six hundred forty-two million, five hundred fifty-seven thousand, five hundred sixty-one".