1215113551 has 2 divisors, whose sum is σ = 1215113552. Its totient is φ = 1215113550.

The previous prime is 1215113531. The next prime is 1215113569. The reversal of 1215113551 is 1553115121.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1215113551 - 2⁷ = 1215113423 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1215113531) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 607556775 + 607556776.

It is an arithmetic number, because the mean of its divisors is an integer number (607556776).

Almost surely, 2^1215113551 is an apocalyptic number.

1215113551 is a deficient number, since it is larger than the sum of its proper divisors (1).

1215113551 is an equidigital number, since it uses as much as digits as its factorization.

1215113551 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 750, while the sum is 25.

The square root of 1215113551 is about 34858.4788968194. The cubic root of 1215113551 is about 1067.1012321874.

Adding to 1215113551 its reverse (1553115121), we get a palindrome (2768228672).

The spelling of 1215113551 in words is "one billion, two hundred fifteen million, one hundred thirteen thousand, five hundred fifty-one".