20873680493 has 4 divisors (see below), whose sum is σ = 20979638460. Its totient is φ = 20767722528.

The previous prime is 20873680489. The next prime is 20873680501. The reversal of 20873680493 is 39408637802.

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

It can be written as a sum of positive squares in 2 ways, for example, as 13298241124 + 7575439369 = 115318^2 + 87037^2 .

It is a cyclic number.

It is not a de Polignac number, because 20873680493 - 2² = 20873680489 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20873682493) 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, 52978688 + ... + 52979081.

It is an arithmetic number, because the mean of its divisors is an integer number (5244909615).

Almost surely, 2^20873680493 is an apocalyptic number.

It is an amenable number.

20873680493 is a deficient number, since it is larger than the sum of its proper divisors (105957967).

20873680493 is a wasteful number, since it uses less digits than its factorization.

20873680493 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 105957966.

The product of its (nonzero) digits is 1741824, while the sum is 50.

The spelling of 20873680493 in words is "twenty billion, eight hundred seventy-three million, six hundred eighty thousand, four hundred ninety-three".