49789981 has 2 divisors, whose sum is σ = 49789982. Its totient is φ = 49789980.

The previous prime is 49789979. The next prime is 49790021. The reversal of 49789981 is 18998794.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 46308025 + 3481956 = 6805^2 + 1866^2 .

It is a cyclic number.

It is not a de Polignac number, because 49789981 - 2¹ = 49789979 is a prime.

It is a super-2 number, since 2×49789981² = 4958084415960722, which contains 22 as substring.

Together with 49789979, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (49789931) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 24894990 + 24894991.

It is an arithmetic number, because the mean of its divisors is an integer number (24894991).

Almost surely, 2^49789981 is an apocalyptic number.

It is an amenable number.

49789981 is a deficient number, since it is larger than the sum of its proper divisors (1).

49789981 is an equidigital number, since it uses as much as digits as its factorization.

49789981 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1306368, while the sum is 55.

The square root of 49789981 is about 7056.2015985940. The cubic root of 49789981 is about 367.8866148990.

The spelling of 49789981 in words is "forty-nine million, seven hundred eighty-nine thousand, nine hundred eighty-one".