1215966825 has 18 divisors (see below), whose sum is σ = 2177932094. Its totient is φ = 648515520.

The previous prime is 1215966823. The next prime is 1215966841. The reversal of 1215966825 is 5286695121.

It can be written as a sum of positive squares in 3 ways, for example, as 18045504 + 1197921321 = 4248^2 + 34611^2 .

It is not a de Polignac number, because 1215966825 - 2¹ = 1215966823 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1215966823) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 2701924 + ... + 2702373.

Almost surely, 2^1215966825 is an apocalyptic number.

1215966825 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1215966825 is a deficient number, since it is larger than the sum of its proper divisors (961965269).

1215966825 is a wasteful number, since it uses less digits than its factorization.

1215966825 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5404313 (or 5404305 counting only the distinct ones).

The product of its digits is 259200, while the sum is 45.

The square root of 1215966825 is about 34870.7158658953. The cubic root of 1215966825 is about 1067.3509527969.

The spelling of 1215966825 in words is "one billion, two hundred fifteen million, nine hundred sixty-six thousand, eight hundred twenty-five".