1215042021 has 12 divisors (see below), whose sum is σ = 1755393120. Its totient is φ = 809874600.

The previous prime is 1215042007. The next prime is 1215042053. The reversal of 1215042021 is 1202405121.

1215042021 is a `hidden beast` number, since 121 + 504 + 20 + 21 = 666.

It is not a de Polignac number, because 1215042021 - 2¹⁰ = 1215040997 is a prime.

It is a super-2 number, since 2×1215042021² = 2952654225591528882, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1215041985 and 1215042003.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1215042121) 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 11 ways as a sum of consecutive naturals, for example, 58000 + ... + 76118.

It is an arithmetic number, because the mean of its divisors is an integer number (146282760).

Almost surely, 2^1215042021 is an apocalyptic number.

It is an amenable number.

1215042021 is a deficient number, since it is larger than the sum of its proper divisors (540351099).

1215042021 is a wasteful number, since it uses less digits than its factorization.

1215042021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25576 (or 25573 counting only the distinct ones).

The product of its (nonzero) digits is 160, while the sum is 18.

The square root of 1215042021 is about 34857.4528759633. The cubic root of 1215042021 is about 1067.0802927866.

Adding to 1215042021 its reverse (1202405121), we get a palindrome (2417447142).

The spelling of 1215042021 in words is "one billion, two hundred fifteen million, forty-two thousand, twenty-one".