1215541849 has 2 divisors, whose sum is σ = 1215541850. Its totient is φ = 1215541848.

The previous prime is 1215541793. The next prime is 1215541897. The reversal of 1215541849 is 9481455121.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 864654025 + 350887824 = 29405^2 + 18732^2 .

It is a cyclic number.

It is not a de Polignac number, because 1215541849 - 2¹⁵ = 1215509081 is a prime.

It is not a weakly prime, because it can be changed into another prime (1215541049) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 607770924 + 607770925.

It is an arithmetic number, because the mean of its divisors is an integer number (607770925).

Almost surely, 2^1215541849 is an apocalyptic number.

It is an amenable number.

1215541849 is a deficient number, since it is larger than the sum of its proper divisors (1).

1215541849 is an equidigital number, since it uses as much as digits as its factorization.

1215541849 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 57600, while the sum is 40.

The square root of 1215541849 is about 34864.6217389491. The cubic root of 1215541849 is about 1067.2265932110.

The spelling of 1215541849 in words is "one billion, two hundred fifteen million, five hundred forty-one thousand, eight hundred forty-nine".