49921 has 2 divisors, whose sum is σ = 49922. Its totient is φ = 49920.

The previous prime is 49919. The next prime is 49927. The reversal of 49921 is 12994.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 48400 + 1521 = 220^2 + 39^2 .

It is a cyclic number.

It is not a de Polignac number, because 49921 - 2¹ = 49919 is a prime.

Together with 49919, it forms a pair of twin primes.

49921 is a lucky number.

It is not a weakly prime, because it can be changed into another prime (49927) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 24960 + 24961.

It is an arithmetic number, because the mean of its divisors is an integer number (24961).

It is a Proth number, since it is equal to 195 ⋅ 2⁸ + 1 and 195 < 2⁸.

2⁴⁹⁹²¹ is an apocalyptic number.

It is an amenable number.

49921 is a deficient number, since it is larger than the sum of its proper divisors (1).

49921 is an equidigital number, since it uses as much as digits as its factorization.

49921 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 648, while the sum is 25.

The square root of 49921 is about 223.4300785481. The cubic root of 49921 is about 36.8209021928.

The spelling of 49921 in words is "forty-nine thousand, nine hundred twenty-one".