149561 has 2 divisors, whose sum is σ = 149562. Its totient is φ = 149560.

The previous prime is 149551. The next prime is 149563. The reversal of 149561 is 165941.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 109561 + 40000 = 331^2 + 200^2 .

It is an emirp because it is prime and its reverse (165941) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 149561 - 2⁶ = 149497 is a prime.

Together with 149563, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 149561.

It is not a weakly prime, because it can be changed into another prime (149563) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 74780 + 74781.

It is an arithmetic number, because the mean of its divisors is an integer number (74781).

2¹⁴⁹⁵⁶¹ is an apocalyptic number.

It is an amenable number.

149561 is a deficient number, since it is larger than the sum of its proper divisors (1).

149561 is an equidigital number, since it uses as much as digits as its factorization.

149561 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1080, while the sum is 26.

The square root of 149561 is about 386.7311727803. The cubic root of 149561 is about 53.0810436861.

The spelling of 149561 in words is "one hundred forty-nine thousand, five hundred sixty-one".