20405057393 has 4 divisors (see below), whose sum is σ = 23320065600. Its totient is φ = 17490049188.

The previous prime is 20405057389. The next prime is 20405057411. The reversal of 20405057393 is 39375050402.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 39375050402 = 2 ⋅19687525201.

It is a cyclic number.

It is not a de Polignac number, because 20405057393 - 2² = 20405057389 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20405057383) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1457504093 + ... + 1457504106.

It is an arithmetic number, because the mean of its divisors is an integer number (5830016400).

Almost surely, 2^20405057393 is an apocalyptic number.

It is an amenable number.

20405057393 is a deficient number, since it is larger than the sum of its proper divisors (2915008207).

20405057393 is an equidigital number, since it uses as much as digits as its factorization.

20405057393 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2915008206.

The product of its (nonzero) digits is 113400, while the sum is 38.

The spelling of 20405057393 in words is "twenty billion, four hundred five million, fifty-seven thousand, three hundred ninety-three".