1242180581 has 2 divisors, whose sum is σ = 1242180582. Its totient is φ = 1242180580.

The previous prime is 1242180503. The next prime is 1242180593. The reversal of 1242180581 is 1850812421.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 843379681 + 398800900 = 29041^2 + 19970^2 .

It is an emirp because it is prime and its reverse (1850812421) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1242180581 - 2¹⁰ = 1242179557 is a prime.

It is a super-2 number, since 2×1242180581² = 3086025191626995122, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1242180281) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 621090290 + 621090291.

It is an arithmetic number, because the mean of its divisors is an integer number (621090291).

Almost surely, 2^1242180581 is an apocalyptic number.

It is an amenable number.

1242180581 is a deficient number, since it is larger than the sum of its proper divisors (1).

1242180581 is an equidigital number, since it uses as much as digits as its factorization.

1242180581 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5120, while the sum is 32.

The square root of 1242180581 is about 35244.5822928858. The cubic root of 1242180581 is about 1074.9664546230.

The spelling of 1242180581 in words is "one billion, two hundred forty-two million, one hundred eighty thousand, five hundred eighty-one".