20840741 has 4 divisors (see below), whose sum is σ = 21055692. Its totient is φ = 20625792.

The previous prime is 20840717. The next prime is 20840761. The reversal of 20840741 is 14704802.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 16638241 + 4202500 = 4079^2 + 2050^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20840741 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20840741.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20840761) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 107330 + ... + 107523.

It is an arithmetic number, because the mean of its divisors is an integer number (5263923).

Almost surely, 2^20840741 is an apocalyptic number.

It is an amenable number.

20840741 is a deficient number, since it is larger than the sum of its proper divisors (214951).

20840741 is an equidigital number, since it uses as much as digits as its factorization.

20840741 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 214950.

The product of its (nonzero) digits is 1792, while the sum is 26.

The square root of 20840741 is about 4565.1660429824. The cubic root of 20840741 is about 275.1932129785.

The spelling of 20840741 in words is "twenty million, eight hundred forty thousand, seven hundred forty-one".