1555355849 has 2 divisors, whose sum is σ = 1555355850. Its totient is φ = 1555355848.

The previous prime is 1555355801. The next prime is 1555355873. The reversal of 1555355849 is 9485535551.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1245595849 + 309760000 = 35293^2 + 17600^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1555355849 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 1555355797 and 1555355806.

It is not a weakly prime, because it can be changed into another prime (1555355149) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 777677924 + 777677925.

It is an arithmetic number, because the mean of its divisors is an integer number (777677925).

Almost surely, 2^1555355849 is an apocalyptic number.

It is an amenable number.

1555355849 is a deficient number, since it is larger than the sum of its proper divisors (1).

1555355849 is an equidigital number, since it uses as much as digits as its factorization.

1555355849 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2700000, while the sum is 50.

The square root of 1555355849 is about 39438.0000633906. Note that the first 4 decimals coincide. The cubic root of 1555355849 is about 1158.6259615085.

The spelling of 1555355849 in words is "one billion, five hundred fifty-five million, three hundred fifty-five thousand, eight hundred forty-nine".