1081555729 has 2 divisors, whose sum is σ = 1081555730. Its totient is φ = 1081555728.

The previous prime is 1081555633. The next prime is 1081555747. The reversal of 1081555729 is 9275551801.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1080634129 + 921600 = 32873^2 + 960^2 .

It is a cyclic number.

It is not a de Polignac number, because 1081555729 - 2²¹ = 1079458577 is a prime.

It is not a weakly prime, because it can be changed into another prime (1081559729) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 540777864 + 540777865.

It is an arithmetic number, because the mean of its divisors is an integer number (540777865).

Almost surely, 2^1081555729 is an apocalyptic number.

It is an amenable number.

1081555729 is a deficient number, since it is larger than the sum of its proper divisors (1).

1081555729 is an equidigital number, since it uses as much as digits as its factorization.

1081555729 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 126000, while the sum is 43.

The square root of 1081555729 is about 32887.0145954296. The cubic root of 1081555729 is about 1026.4779722342.

The spelling of 1081555729 in words is "one billion, eighty-one million, five hundred fifty-five thousand, seven hundred twenty-nine".