1215656642 has 8 divisors (see below), whose sum is σ = 1867960332. Its totient is φ = 593003200.

The previous prime is 1215656633. The next prime is 1215656657. The reversal of 1215656642 is 2466565121.

It can be written as a sum of positive squares in 2 ways, for example, as 949934041 + 265722601 = 30821^2 + 16301^2 .

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

It is a junction number, because it is equal to n+sod(n) for n = 1215656596 and 1215656605.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7412459 + ... + 7412622.

Almost surely, 2^1215656642 is an apocalyptic number.

1215656642 is a deficient number, since it is larger than the sum of its proper divisors (652303690).

1215656642 is a wasteful number, since it uses less digits than its factorization.

1215656642 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14825124.

The product of its digits is 86400, while the sum is 38.

The square root of 1215656642 is about 34866.2679677651. The cubic root of 1215656642 is about 1067.2601876354.

The spelling of 1215656642 in words is "one billion, two hundred fifteen million, six hundred fifty-six thousand, six hundred forty-two".