1155421105 has 4 divisors (see below), whose sum is σ = 1386505332. Its totient is φ = 924336880.

The previous prime is 1155421093. The next prime is 1155421153. The reversal of 1155421105 is 5011245511.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 647549809 + 507871296 = 25447^2 + 22536^2 .

It is not a de Polignac number, because 1155421105 - 2²⁵ = 1121866673 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1155421105.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 115542106 + ... + 115542115.

It is an arithmetic number, because the mean of its divisors is an integer number (346626333).

Almost surely, 2^1155421105 is an apocalyptic number.

It is an amenable number.

1155421105 is a deficient number, since it is larger than the sum of its proper divisors (231084227).

1155421105 is an equidigital number, since it uses as much as digits as its factorization.

1155421105 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 231084226.

The product of its (nonzero) digits is 1000, while the sum is 25.

The square root of 1155421105 is about 33991.4857721754. The cubic root of 1155421105 is about 1049.3332441184. Note that the first 3 decimals are identical.

Adding to 1155421105 its reverse (5011245511), we get a palindrome (6166666616).

The spelling of 1155421105 in words is "one billion, one hundred fifty-five million, four hundred twenty-one thousand, one hundred five".