15540251 has 2 divisors, whose sum is σ = 15540252. Its totient is φ = 15540250.

The previous prime is 15540241. The next prime is 15540277. The reversal of 15540251 is 15204551.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 15540251 - 2¹⁴ = 15523867 is a prime.

It is a super-2 number, since 2×15540251² = 482998802286002, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (15540211) 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, 7770125 + 7770126.

It is an arithmetic number, because the mean of its divisors is an integer number (7770126).

Almost surely, 2^15540251 is an apocalyptic number.

15540251 is a deficient number, since it is larger than the sum of its proper divisors (1).

15540251 is an equidigital number, since it uses as much as digits as its factorization.

15540251 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1000, while the sum is 23.

The square root of 15540251 is about 3942.1125047365. The cubic root of 15540251 is about 249.5471856652.

The spelling of 15540251 in words is "fifteen million, five hundred forty thousand, two hundred fifty-one".