1215655643 has 2 divisors, whose sum is σ = 1215655644. Its totient is φ = 1215655642.

The previous prime is 1215655627. The next prime is 1215655657. The reversal of 1215655643 is 3465565121.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1215655643 - 2⁴ = 1215655627 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1215655597 and 1215655606.

It is not a weakly prime, because it can be changed into another prime (1215655613) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 607827821 + 607827822.

It is an arithmetic number, because the mean of its divisors is an integer number (607827822).

Almost surely, 2^1215655643 is an apocalyptic number.

1215655643 is a deficient number, since it is larger than the sum of its proper divisors (1).

1215655643 is an equidigital number, since it uses as much as digits as its factorization.

1215655643 is an evil number, because the sum of its binary digits is even.

The product of its digits is 108000, while the sum is 38.

The square root of 1215655643 is about 34866.2536415945. The cubic root of 1215655643 is about 1067.2598952849.

The spelling of 1215655643 in words is "one billion, two hundred fifteen million, six hundred fifty-five thousand, six hundred forty-three".