1212816461 has 2 divisors, whose sum is σ = 1212816462. Its totient is φ = 1212816460.

The previous prime is 1212816443. The next prime is 1212816481. The reversal of 1212816461 is 1646182121.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 616528900 + 596287561 = 24830^2 + 24419^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1212816461 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1212816421) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 606408230 + 606408231.

It is an arithmetic number, because the mean of its divisors is an integer number (606408231).

Almost surely, 2^1212816461 is an apocalyptic number.

It is an amenable number.

1212816461 is a deficient number, since it is larger than the sum of its proper divisors (1).

1212816461 is an equidigital number, since it uses as much as digits as its factorization.

1212816461 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4608, while the sum is 32.

The square root of 1212816461 is about 34825.5145116336. The cubic root of 1212816461 is about 1066.4283804421.

Adding to 1212816461 its reverse (1646182121), we get a palindrome (2858998582).

The spelling of 1212816461 in words is "one billion, two hundred twelve million, eight hundred sixteen thousand, four hundred sixty-one".