20857923542 has 4 divisors (see below), whose sum is σ = 31286885316. Its totient is φ = 10428961770.

The previous prime is 20857923517. The next prime is 20857923557. The reversal of 20857923542 is 24532975802.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5214480884 + ... + 5214480887.

It is an arithmetic number, because the mean of its divisors is an integer number (7821721329).

Almost surely, 2^20857923542 is an apocalyptic number.

20857923542 is a deficient number, since it is larger than the sum of its proper divisors (10428961774).

20857923542 is a wasteful number, since it uses less digits than its factorization.

20857923542 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10428961773.

The product of its (nonzero) digits is 1209600, while the sum is 47.

The spelling of 20857923542 in words is "twenty billion, eight hundred fifty-seven million, nine hundred twenty-three thousand, five hundred forty-two".