20745923 has 4 divisors (see below), whose sum is σ = 22631928. Its totient is φ = 18859920.

The previous prime is 20745911. The next prime is 20745971. The reversal of 20745923 is 32954702.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 20745923 - 2⁸ = 20745667 is a prime.

It is a super-2 number, since 2×20745923² = 860786642243858, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 20745923.

It is not an unprimeable number, because it can be changed into a prime (20745973) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 942986 + ... + 943007.

It is an arithmetic number, because the mean of its divisors is an integer number (5657982).

Almost surely, 2^20745923 is an apocalyptic number.

20745923 is a deficient number, since it is larger than the sum of its proper divisors (1886005).

20745923 is a wasteful number, since it uses less digits than its factorization.

20745923 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1886004.

The product of its (nonzero) digits is 15120, while the sum is 32.

The square root of 20745923 is about 4554.7692587002. The cubic root of 20745923 is about 274.7752345245.

It can be divided in two parts, 2074 and 5923, that added together give a palindrome (7997).

The spelling of 20745923 in words is "twenty million, seven hundred forty-five thousand, nine hundred twenty-three".