20457403 has 4 divisors (see below), whose sum is σ = 20479320. Its totient is φ = 20435488.

The previous prime is 20457391. The next prime is 20457413. The reversal of 20457403 is 30475402.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 30475402 = 2 ⋅15237701.

It is a cyclic number.

It is not a de Polignac number, because 20457403 - 2¹³ = 20449211 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20457413) 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, 9493 + ... + 11446.

It is an arithmetic number, because the mean of its divisors is an integer number (5119830).

Almost surely, 2^20457403 is an apocalyptic number.

20457403 is a deficient number, since it is larger than the sum of its proper divisors (21917).

20457403 is an equidigital number, since it uses as much as digits as its factorization.

20457403 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21916.

The product of its (nonzero) digits is 3360, while the sum is 25.

The square root of 20457403 is about 4522.9860711702. The cubic root of 20457403 is about 273.4954885862.

The spelling of 20457403 in words is "twenty million, four hundred fifty-seven thousand, four hundred three".