15215281 has 2 divisors, whose sum is σ = 15215282. Its totient is φ = 15215280.

The previous prime is 15215279. The next prime is 15215287. The reversal of 15215281 is 18251251.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 13024881 + 2190400 = 3609^2 + 1480^2 .

It is a cyclic number.

It is not a de Polignac number, because 15215281 - 2¹ = 15215279 is a prime.

It is a super-2 number, since 2×15215281² = 463009551817922, which contains 22 as substring.

Together with 15215279, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (15215287) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7607640 + 7607641.

It is an arithmetic number, because the mean of its divisors is an integer number (7607641).

Almost surely, 2^15215281 is an apocalyptic number.

It is an amenable number.

15215281 is a deficient number, since it is larger than the sum of its proper divisors (1).

15215281 is an equidigital number, since it uses as much as digits as its factorization.

15215281 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 800, while the sum is 25.

The square root of 15215281 is about 3900.6769925232. The cubic root of 15215281 is about 247.7954489614.

It can be divided in two parts, 15 and 215281, that added together give a square (215296 = 464²).

The spelling of 15215281 in words is "fifteen million, two hundred fifteen thousand, two hundred eighty-one".