1215231601 has 2 divisors, whose sum is σ = 1215231602. Its totient is φ = 1215231600.

The previous prime is 1215231593. The next prime is 1215231623. The reversal of 1215231601 is 1061325121.

It is a happy number.

It is an a-pointer prime, because the next prime (1215231623) can be obtained adding 1215231601 to its sum of digits (22).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 810256225 + 404975376 = 28465^2 + 20124^2 .

It is an emirp because it is prime and its reverse (1061325121) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1215231601 - 2³ = 1215231593 is a prime.

It is not a weakly prime, because it can be changed into another prime (1215231001) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 607615800 + 607615801.

It is an arithmetic number, because the mean of its divisors is an integer number (607615801).

Almost surely, 2^1215231601 is an apocalyptic number.

It is an amenable number.

1215231601 is a deficient number, since it is larger than the sum of its proper divisors (1).

1215231601 is an equidigital number, since it uses as much as digits as its factorization.

1215231601 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 360, while the sum is 22.

The square root of 1215231601 is about 34860.1721309577. The cubic root of 1215231601 is about 1067.1357878663.

Adding to 1215231601 its reverse (1061325121), we get a palindrome (2276556722).

The spelling of 1215231601 in words is "one billion, two hundred fifteen million, two hundred thirty-one thousand, six hundred one".