1253563121 has 4 divisors (see below), whose sum is σ = 1253690100. Its totient is φ = 1253436144.

The previous prime is 1253563117. The next prime is 1253563159. The reversal of 1253563121 is 1213653521.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1213653521 = 34519 ⋅35159.

It can be written as a sum of positive squares in 2 ways, for example, as 357399025 + 896164096 = 18905^2 + 29936^2 .

It is a cyclic number.

It is not a de Polignac number, because 1253563121 - 2² = 1253563117 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1253563321) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 47306 + ... + 68883.

It is an arithmetic number, because the mean of its divisors is an integer number (313422525).

Almost surely, 2^1253563121 is an apocalyptic number.

It is an amenable number.

1253563121 is a deficient number, since it is larger than the sum of its proper divisors (126979).

1253563121 is a wasteful number, since it uses less digits than its factorization.

1253563121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 126978.

The product of its digits is 5400, while the sum is 29.

The square root of 1253563121 is about 35405.6933416082. The cubic root of 1253563121 is about 1078.2399088905.

The spelling of 1253563121 in words is "one billion, two hundred fifty-three million, five hundred sixty-three thousand, one hundred twenty-one".