149921 has 2 divisors, whose sum is σ = 149922. Its totient is φ = 149920.

The previous prime is 149911. The next prime is 149939. The reversal of 149921 is 129941.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 130321 + 19600 = 361^2 + 140^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-149921 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (149911) 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, 74960 + 74961.

It is an arithmetic number, because the mean of its divisors is an integer number (74961).

2¹⁴⁹⁹²¹ is an apocalyptic number.

It is an amenable number.

149921 is a deficient number, since it is larger than the sum of its proper divisors (1).

149921 is an equidigital number, since it uses as much as digits as its factorization.

149921 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 648, while the sum is 26.

The square root of 149921 is about 387.1963326273. The cubic root of 149921 is about 53.1235990403.

The spelling of 149921 in words is "one hundred forty-nine thousand, nine hundred twenty-one".