15561253 has 2 divisors, whose sum is σ = 15561254. Its totient is φ = 15561252.

The previous prime is 15561251. The next prime is 15561281. The reversal of 15561253 is 35216551.

It is an a-pointer prime, because the next prime (15561281) can be obtained adding 15561253 to its sum of digits (28).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 10099684 + 5461569 = 3178^2 + 2337^2 .

It is an emirp because it is prime and its reverse (35216551) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 15561253 - 2¹ = 15561251 is a prime.

Together with 15561251, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (15561251) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7780626 + 7780627.

It is an arithmetic number, because the mean of its divisors is an integer number (7780627).

Almost surely, 2^15561253 is an apocalyptic number.

It is an amenable number.

15561253 is a deficient number, since it is larger than the sum of its proper divisors (1).

15561253 is an equidigital number, since it uses as much as digits as its factorization.

15561253 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4500, while the sum is 28.

The square root of 15561253 is about 3944.7754055206. The cubic root of 15561253 is about 249.6595525927.

It can be divided in two parts, 1556 and 1253, that added together give a square (2809 = 53²).

The spelling of 15561253 in words is "fifteen million, five hundred sixty-one thousand, two hundred fifty-three".