1045556581 has 2 divisors, whose sum is σ = 1045556582. Its totient is φ = 1045556580.

The previous prime is 1045556543. The next prime is 1045556647. The reversal of 1045556581 is 1856555401.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1045552225 + 4356 = 32335^2 + 66^2 .

It is a cyclic number.

It is not a de Polignac number, because 1045556581 - 2¹³ = 1045548389 is a prime.

It is a super-2 number, since 2×1045556581² = 2186377128144819122, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1045556081) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 522778290 + 522778291.

It is an arithmetic number, because the mean of its divisors is an integer number (522778291).

Almost surely, 2^1045556581 is an apocalyptic number.

It is an amenable number.

1045556581 is a deficient number, since it is larger than the sum of its proper divisors (1).

1045556581 is an equidigital number, since it uses as much as digits as its factorization.

1045556581 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 120000, while the sum is 40.

The square root of 1045556581 is about 32335.0673572826. The cubic root of 1045556581 is about 1014.9605915443.

The spelling of 1045556581 in words is "one billion, forty-five million, five hundred fifty-six thousand, five hundred eighty-one".