1021243253 has 4 divisors (see below), whose sum is σ = 1048844460. Its totient is φ = 993642048.

The previous prime is 1021243241. The next prime is 1021243259. The reversal of 1021243253 is 3523421201.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 3523421201 = 53993 ⋅65257.

It can be written as a sum of positive squares in 2 ways, for example, as 885241009 + 136002244 = 29753^2 + 11662^2 .

It is a cyclic number.

It is not a de Polignac number, because 1021243253 - 2²⁴ = 1004466037 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 (1021243259) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13800548 + ... + 13800621.

It is an arithmetic number, because the mean of its divisors is an integer number (262211115).

Almost surely, 2^1021243253 is an apocalyptic number.

It is an amenable number.

1021243253 is a deficient number, since it is larger than the sum of its proper divisors (27601207).

1021243253 is an equidigital number, since it uses as much as digits as its factorization.

1021243253 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27601206.

The product of its (nonzero) digits is 1440, while the sum is 23.

The square root of 1021243253 is about 31956.8967986568. The cubic root of 1021243253 is about 1007.0315260891.

Adding to 1021243253 its reverse (3523421201), we get a palindrome (4544664454).

The spelling of 1021243253 in words is "one billion, twenty-one million, two hundred forty-three thousand, two hundred fifty-three".