15555251 has 2 divisors, whose sum is σ = 15555252. Its totient is φ = 15555250.

The previous prime is 15555247. The next prime is 15555263. The reversal of 15555251 is 15255551.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 15555251 - 2² = 15555247 is a prime.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (15555151) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7777625 + 7777626.

It is an arithmetic number, because the mean of its divisors is an integer number (7777626).

Almost surely, 2^15555251 is an apocalyptic number.

15555251 is a deficient number, since it is larger than the sum of its proper divisors (1).

15555251 is an equidigital number, since it uses as much as digits as its factorization.

15555251 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6250, while the sum is 29.

The square root of 15555251 is about 3944.0145790806. The cubic root of 15555251 is about 249.6274504364.

The spelling of 15555251 in words is "fifteen million, five hundred fifty-five thousand, two hundred fifty-one".