1155152221 has 2 divisors, whose sum is σ = 1155152222. Its totient is φ = 1155152220.

The previous prime is 1155152189. The next prime is 1155152231. The reversal of 1155152221 is 1222515511.

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., 1146567321 + 8584900 = 33861^2 + 2930^2 .

It is a cyclic number.

It is not a de Polignac number, because 1155152221 - 2⁵ = 1155152189 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1155152231) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 577576110 + 577576111.

It is an arithmetic number, because the mean of its divisors is an integer number (577576111).

Almost surely, 2^1155152221 is an apocalyptic number.

It is an amenable number.

1155152221 is a deficient number, since it is larger than the sum of its proper divisors (1).

1155152221 is an equidigital number, since it uses as much as digits as its factorization.

1155152221 is an evil number, because the sum of its binary digits is even.

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

The square root of 1155152221 is about 33987.5303751243. The cubic root of 1155152221 is about 1049.2518392210.

Adding to 1155152221 its reverse (1222515511), we get a palindrome (2377667732).

The spelling of 1155152221 in words is "one billion, one hundred fifty-five million, one hundred fifty-two thousand, two hundred twenty-one".