1215312725 has 24 divisors (see below), whose sum is σ = 1649706912. Its totient is φ = 880788800.

The previous prime is 1215312719. The next prime is 1215312727. The reversal of 1215312725 is 5272135121.

It is not a de Polignac number, because 1215312725 - 2⁶ = 1215312661 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1215312727) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 73034 + ... + 88116.

It is an arithmetic number, because the mean of its divisors is an integer number (68737788).

Almost surely, 2^1215312725 is an apocalyptic number.

It is an amenable number.

1215312725 is a deficient number, since it is larger than the sum of its proper divisors (434394187).

1215312725 is a wasteful number, since it uses less digits than its factorization.

1215312725 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15397 (or 15392 counting only the distinct ones).

The product of its digits is 4200, while the sum is 29.

The square root of 1215312725 is about 34861.3356743542. The cubic root of 1215312725 is about 1067.1595332433.

Adding to 1215312725 its reverse (5272135121), we get a palindrome (6487447846).

The spelling of 1215312725 in words is "one billion, two hundred fifteen million, three hundred twelve thousand, seven hundred twenty-five".