102445561 has 2 divisors, whose sum is σ = 102445562. Its totient is φ = 102445560.

The previous prime is 102445559. The next prime is 102445573. The reversal of 102445561 is 165544201.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 53934336 + 48511225 = 7344^2 + 6965^2 .

It is an emirp because it is prime and its reverse (165544201) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 102445561 - 2¹ = 102445559 is a prime.

Together with 102445559, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (102445591) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 51222780 + 51222781.

It is an arithmetic number, because the mean of its divisors is an integer number (51222781).

Almost surely, 2^102445561 is an apocalyptic number.

It is an amenable number.

102445561 is a deficient number, since it is larger than the sum of its proper divisors (1).

102445561 is an equidigital number, since it uses as much as digits as its factorization.

102445561 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4800, while the sum is 28.

The square root of 102445561 is about 10121.5394580074. The cubic root of 102445561 is about 467.9122138531.

Adding to 102445561 its reverse (165544201), we get a palindrome (267989762).

The spelling of 102445561 in words is "one hundred two million, four hundred forty-five thousand, five hundred sixty-one".