20840704 has 18 divisors (see below), whose sum is σ = 41600510. Its totient is φ = 10420224.

The previous prime is 20840683. The next prime is 20840707. The reversal of 20840704 is 40704802.

It can be written as a sum of positive squares in only one way, i.e., 16646400 + 4194304 = 4080^2 + 2048^2 .

It is not an unprimeable number, because it can be changed into a prime (20840707) 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, 40449 + ... + 40960.

Almost surely, 2^20840704 is an apocalyptic number.

It is an amenable number.

20840704 is a deficient number, since it is larger than the sum of its proper divisors (20759806).

20840704 is an frugal number, since it uses more digits than its factorization.

20840704 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 81425 (or 81411 counting only the distinct ones).

The product of its (nonzero) digits is 1792, while the sum is 25.

The square root of 20840704 is about 4565.1619905541. The cubic root of 20840704 is about 275.1930501219.

The spelling of 20840704 in words is "twenty million, eight hundred forty thousand, seven hundred four".