20857820142 has 8 divisors (see below), whose sum is σ = 41715640296. Its totient is φ = 6952606712.

The previous prime is 20857820119. The next prime is 20857820189. The reversal of 20857820142 is 24102875802.

It is a sphenic number, since it is the product of 3 distinct primes.

20857820142 is an admirable number.

It is a super-2 number, since 2×20857820142² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 20857820142.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1738151673 + ... + 1738151684.

It is an arithmetic number, because the mean of its divisors is an integer number (5214455037).

Almost surely, 2^20857820142 is an apocalyptic number.

20857820142 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20857820142 is a wasteful number, since it uses less digits than its factorization.

20857820142 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3476303362.

The product of its (nonzero) digits is 71680, while the sum is 39.

The spelling of 20857820142 in words is "twenty billion, eight hundred fifty-seven million, eight hundred twenty thousand, one hundred forty-two".