1215512461 has 8 divisors (see below), whose sum is σ = 1287374904. Its totient is φ = 1143690240.

The previous prime is 1215512453. The next prime is 1215512471. The reversal of 1215512461 is 1642155121.

It can be written as a sum of positive squares in 4 ways, for example, as 218152900 + 997359561 = 14770^2 + 31581^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1215512461 - 2³ = 1215512453 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1215512471) 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 in 7 ways as a sum of consecutive naturals, for example, 70821 + ... + 86293.

It is an arithmetic number, because the mean of its divisors is an integer number (160921863).

Almost surely, 2^1215512461 is an apocalyptic number.

It is an amenable number.

1215512461 is a deficient number, since it is larger than the sum of its proper divisors (71862443).

1215512461 is a wasteful number, since it uses less digits than its factorization.

1215512461 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20111.

The product of its digits is 2400, while the sum is 28.

The square root of 1215512461 is about 34864.2002776487. The cubic root of 1215512461 is about 1067.2179924080.

Adding to 1215512461 its reverse (1642155121), we get a palindrome (2857667582).

The spelling of 1215512461 in words is "one billion, two hundred fifteen million, five hundred twelve thousand, four hundred sixty-one".