101245561 has 2 divisors, whose sum is σ = 101245562. Its totient is φ = 101245560.

The previous prime is 101245559. The next prime is 101245633. The reversal of 101245561 is 165542101.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 60528400 + 40717161 = 7780^2 + 6381^2 .

It is an emirp because it is prime and its reverse (165542101) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 101245561 - 2¹ = 101245559 is a prime.

Together with 101245559, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (101245961) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 50622780 + 50622781.

It is an arithmetic number, because the mean of its divisors is an integer number (50622781).

Almost surely, 2^101245561 is an apocalyptic number.

It is an amenable number.

101245561 is a deficient number, since it is larger than the sum of its proper divisors (1).

101245561 is an equidigital number, since it uses as much as digits as its factorization.

101245561 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1200, while the sum is 25.

The square root of 101245561 is about 10062.0853206480. The cubic root of 101245561 is about 466.0780644330.

Adding to 101245561 its reverse (165542101), we get a palindrome (266787662).

The spelling of 101245561 in words is "one hundred one million, two hundred forty-five thousand, five hundred sixty-one".