1155544421 has 2 divisors, whose sum is σ = 1155544422. Its totient is φ = 1155544420.

The previous prime is 1155544399. The next prime is 1155544427. The reversal of 1155544421 is 1244455511.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 678602500 + 476941921 = 26050^2 + 21839^2 .

It is a cyclic number.

It is not a de Polignac number, because 1155544421 - 2¹⁴ = 1155528037 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1155544427) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 577772210 + 577772211.

It is an arithmetic number, because the mean of its divisors is an integer number (577772211).

Almost surely, 2^1155544421 is an apocalyptic number.

It is an amenable number.

1155544421 is a deficient number, since it is larger than the sum of its proper divisors (1).

1155544421 is an equidigital number, since it uses as much as digits as its factorization.

1155544421 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 16000, while the sum is 32.

The square root of 1155544421 is about 33993.2996486072. The cubic root of 1155544421 is about 1049.3705739354.

Adding to 1155544421 its reverse (1244455511), we get a palindrome (2399999932).

The spelling of 1155544421 in words is "one billion, one hundred fifty-five million, five hundred forty-four thousand, four hundred twenty-one".