42649 has 2 divisors, whose sum is σ = 42650. Its totient is φ = 42648.

The previous prime is 42643. The next prime is 42667. The reversal of 42649 is 94624.

42649 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 38025 + 4624 = 195^2 + 68^2 .

It is a cyclic number.

It is not a de Polignac number, because 42649 - 2³ = 42641 is a prime.

It is a nialpdrome in base 15.

It is not a weakly prime, because it can be changed into another prime (42641) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21324 + 21325.

It is an arithmetic number, because the mean of its divisors is an integer number (21325).

2⁴²⁶⁴⁹ is an apocalyptic number.

It is an amenable number.

42649 is a deficient number, since it is larger than the sum of its proper divisors (1).

42649 is an equidigital number, since it uses as much as digits as its factorization.

42649 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1728, while the sum is 25.

The square root of 42649 is about 206.5163431789. The cubic root of 42649 is about 34.9383950315.

Subtracting from 42649 its sum of digits (25), we obtain a palindrome (42624).

The spelling of 42649 in words is "forty-two thousand, six hundred forty-nine".