1155226021 has 2 divisors, whose sum is σ = 1155226022. Its totient is φ = 1155226020.

The previous prime is 1155226013. The next prime is 1155226069. The reversal of 1155226021 is 1206225511.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1103169796 + 52056225 = 33214^2 + 7215^2 .

It is an emirp because it is prime and its reverse (1206225511) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1155226021 - 2³ = 1155226013 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1155226091) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 577613010 + 577613011.

It is an arithmetic number, because the mean of its divisors is an integer number (577613011).

Almost surely, 2^1155226021 is an apocalyptic number.

It is an amenable number.

1155226021 is a deficient number, since it is larger than the sum of its proper divisors (1).

1155226021 is an equidigital number, since it uses as much as digits as its factorization.

1155226021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1200, while the sum is 25.

The square root of 1155226021 is about 33988.6160500836. The cubic root of 1155226021 is about 1049.2741835018.

It can be divided in two parts, 11552 and 26021, that added together give a palindrome (37573).

The spelling of 1155226021 in words is "one billion, one hundred fifty-five million, two hundred twenty-six thousand, twenty-one".