20743505 has 8 divisors (see below), whose sum is σ = 25030824. Its totient is φ = 16502400.

The previous prime is 20743483. The next prime is 20743517. The reversal of 20743505 is 50534702.

It can be written as a sum of positive squares in 4 ways, for example, as 22801 + 20720704 = 151^2 + 4552^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 20743505 - 2¹⁸ = 20481361 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10556 + ... + 12365.

It is an arithmetic number, because the mean of its divisors is an integer number (3128853).

Almost surely, 2^20743505 is an apocalyptic number.

It is an amenable number.

20743505 is a deficient number, since it is larger than the sum of its proper divisors (4287319).

20743505 is a wasteful number, since it uses less digits than its factorization.

20743505 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23107.

The product of its (nonzero) digits is 4200, while the sum is 26.

The square root of 20743505 is about 4554.5038149067. The cubic root of 20743505 is about 274.7645588152.

The spelling of 20743505 in words is "twenty million, seven hundred forty-three thousand, five hundred five".