20558243623 has 4 divisors (see below), whose sum is σ = 20559604600. Its totient is φ = 20556882648.

The previous prime is 20558243611. The next prime is 20558243647. The reversal of 20558243623 is 32634285502.

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

It is a cyclic number.

It is not a de Polignac number, because 20558243623 - 2⁵ = 20558243591 is a prime.

It is a super-2 number, since 2×20558243623² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20558243653) 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, 657573 + ... + 688126.

It is an arithmetic number, because the mean of its divisors is an integer number (5139901150).

Almost surely, 2^20558243623 is an apocalyptic number.

20558243623 is a deficient number, since it is larger than the sum of its proper divisors (1360977).

20558243623 is a wasteful number, since it uses less digits than its factorization.

20558243623 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1360976.

The product of its (nonzero) digits is 345600, while the sum is 40.

The spelling of 20558243623 in words is "twenty billion, five hundred fifty-eight million, two hundred forty-three thousand, six hundred twenty-three".