20645387193 has 4 divisors (see below), whose sum is σ = 27527182928. Its totient is φ = 13763591460.

The previous prime is 20645387153. The next prime is 20645387239. The reversal of 20645387193 is 39178354602.

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.

It is not a de Polignac number, because 20645387193 - 2³³ = 12055452601 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20645387153) 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, 3440897863 + ... + 3440897868.

It is an arithmetic number, because the mean of its divisors is an integer number (6881795732).

It is a 1-persistent number, because it is pandigital, but 2⋅20645387193 = 41290774386 is not.

Almost surely, 2^20645387193 is an apocalyptic number.

It is an amenable number.

20645387193 is a deficient number, since it is larger than the sum of its proper divisors (6881795735).

20645387193 is an equidigital number, since it uses as much as digits as its factorization.

20645387193 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6881795734.

The product of its (nonzero) digits is 1088640, while the sum is 48.

The spelling of 20645387193 in words is "twenty billion, six hundred forty-five million, three hundred eighty-seven thousand, one hundred ninety-three".