1253320221 has 4 divisors (see below), whose sum is σ = 1671093632. Its totient is φ = 835546812.

The previous prime is 1253320207. The next prime is 1253320249. The reversal of 1253320221 is 1220233521.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 1253320221 - 2¹⁸ = 1253058077 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 (1253310221) 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, 208886701 + ... + 208886706.

It is an arithmetic number, because the mean of its divisors is an integer number (417773408).

Almost surely, 2^1253320221 is an apocalyptic number.

It is an amenable number.

1253320221 is a deficient number, since it is larger than the sum of its proper divisors (417773411).

1253320221 is an equidigital number, since it uses as much as digits as its factorization.

1253320221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 417773410.

The product of its (nonzero) digits is 720, while the sum is 21.

The square root of 1253320221 is about 35402.2629361458. The cubic root of 1253320221 is about 1078.1702617150.

Adding to 1253320221 its reverse (1220233521), we get a palindrome (2473553742).

The spelling of 1253320221 in words is "one billion, two hundred fifty-three million, three hundred twenty thousand, two hundred twenty-one".