1021355243 has 2 divisors, whose sum is σ = 1021355244. Its totient is φ = 1021355242.

The previous prime is 1021355197. The next prime is 1021355249. The reversal of 1021355243 is 3425531201.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1021355243 - 2¹² = 1021351147 is a prime.

It is not a weakly prime, because it can be changed into another prime (1021355249) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 510677621 + 510677622.

It is an arithmetic number, because the mean of its divisors is an integer number (510677622).

Almost surely, 2^1021355243 is an apocalyptic number.

1021355243 is a deficient number, since it is larger than the sum of its proper divisors (1).

1021355243 is an equidigital number, since it uses as much as digits as its factorization.

1021355243 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3600, while the sum is 26.

The square root of 1021355243 is about 31958.6489545475. The cubic root of 1021355243 is about 1007.0683352555.

Adding to 1021355243 its reverse (3425531201), we get a palindrome (4446886444).

It can be divided in two parts, 10213 and 55243, that added together give a palindrome (65456).

The spelling of 1021355243 in words is "one billion, twenty-one million, three hundred fifty-five thousand, two hundred forty-three".