20878679593 has 4 divisors (see below), whose sum is σ = 20904049408. Its totient is φ = 20853309780.

The previous prime is 20878679573. The next prime is 20878679621. The reversal of 20878679593 is 39597687802.

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 a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20878679593 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20878679533) 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, 12683673 + ... + 12685318.

It is an arithmetic number, because the mean of its divisors is an integer number (5226012352).

Almost surely, 2^20878679593 is an apocalyptic number.

It is an amenable number.

20878679593 is a deficient number, since it is larger than the sum of its proper divisors (25369815).

20878679593 is an equidigital number, since it uses as much as digits as its factorization.

20878679593 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25369814.

The product of its (nonzero) digits is 45722880, while the sum is 64.

The spelling of 20878679593 in words is "twenty billion, eight hundred seventy-eight million, six hundred seventy-nine thousand, five hundred ninety-three".