1253563521 has 12 divisors (see below), whose sum is σ = 1944302832. Its totient is φ = 716321928.

The previous prime is 1253563471. The next prime is 1253563537. The reversal of 1253563521 is 1253653521.

It is a happy number.

1253563521 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 1253563521 - 2⁷ = 1253563393 is a prime.

It is a Curzon number.

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

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 4263675 + ... + 4263968.

It is an arithmetic number, because the mean of its divisors is an integer number (162025236).

Almost surely, 2^1253563521 is an apocalyptic number.

It is an amenable number.

1253563521 is a deficient number, since it is larger than the sum of its proper divisors (690739311).

1253563521 is an equidigital number, since it uses as much as digits as its factorization.

1253563521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8527660 (or 8527653 counting only the distinct ones).

The product of its digits is 27000, while the sum is 33.

The square root of 1253563521 is about 35405.6989904168. The cubic root of 1253563521 is about 1078.2400235758.

Subtracting 1253563521 from its reverse (1253653521), we obtain a square (90000 = 300²).

The spelling of 1253563521 in words is "one billion, two hundred fifty-three million, five hundred sixty-three thousand, five hundred twenty-one".