16440251 has 2 divisors, whose sum is σ = 16440252. Its totient is φ = 16440250.

The previous prime is 16440223. The next prime is 16440253. The reversal of 16440251 is 15204461.

It is a strong prime.

It is an emirp because it is prime and its reverse (15204461) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-16440251 is a prime.

It is a super-3 number, since 3×16440251³ (a number of 23 digits) contains 333 as substring.

It is a Sophie Germain prime.

Together with 16440253, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (16440253) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8220125 + 8220126.

It is an arithmetic number, because the mean of its divisors is an integer number (8220126).

Almost surely, 2^16440251 is an apocalyptic number.

16440251 is a deficient number, since it is larger than the sum of its proper divisors (1).

16440251 is an equidigital number, since it uses as much as digits as its factorization.

16440251 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 960, while the sum is 23.

The square root of 16440251 is about 4054.6579387169. The cubic root of 16440251 is about 254.2745032811.

The spelling of 16440251 in words is "sixteen million, four hundred forty thousand, two hundred fifty-one".