20857871872 has 40 divisors (see below), whose sum is σ = 41688878616. Its totient is φ = 10425464832.

The previous prime is 20857871831. The next prime is 20857871873. The reversal of 20857871872 is 27817875802.

It is a super-3 number, since 3×20857871872³ (a number of 32 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20857871873) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2295883 + ... + 2304949.

Almost surely, 2^20857871872 is an apocalyptic number.

It is an amenable number.

20857871872 is a deficient number, since it is larger than the sum of its proper divisors (20831006744).

20857871872 is an frugal number, since it uses more digits than its factorization.

20857871872 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13578 (or 13562 counting only the distinct ones).

The product of its (nonzero) digits is 3512320, while the sum is 55.

The spelling of 20857871872 in words is "twenty billion, eight hundred fifty-seven million, eight hundred seventy-one thousand, eight hundred seventy-two".