1215054161 has 6 divisors (see below), whose sum is σ = 1282370562. Its totient is φ = 1151103600.

The previous prime is 1215054157. The next prime is 1215054163. The reversal of 1215054161 is 1614505121.

It can be written as a sum of positive squares in only one way, i.e., 984014161 + 231040000 = 31369^2 + 15200^2 .

It is not a de Polignac number, because 1215054161 - 2² = 1215054157 is a prime.

It is a super-2 number, since 2×1215054161² = 2952713228326827842, which contains 22 as substring.

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 1215054161.

It is not an unprimeable number, because it can be changed into a prime (1215054163) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1682540 + ... + 1683261.

It is an arithmetic number, because the mean of its divisors is an integer number (213728427).

Almost surely, 2^1215054161 is an apocalyptic number.

It is an amenable number.

1215054161 is a deficient number, since it is larger than the sum of its proper divisors (67316401).

1215054161 is an equidigital number, since it uses as much as digits as its factorization.

1215054161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3365839 (or 3365820 counting only the distinct ones).

The product of its (nonzero) digits is 1200, while the sum is 26.

The square root of 1215054161 is about 34857.6270133238. The cubic root of 1215054161 is about 1067.0838466586.

Adding to 1215054161 its reverse (1614505121), we get a palindrome (2829559282).

The spelling of 1215054161 in words is "one billion, two hundred fifteen million, fifty-four thousand, one hundred sixty-one".