20212738857 has 6 divisors (see below), whose sum is σ = 29196178362. Its totient is φ = 13475159232.

The previous prime is 20212738841. The next prime is 20212738877. The reversal of 20212738857 is 75883721202.

20212738857 is a `hidden beast` number, since 2 + 0 + 212 + 7 + 388 + 57 = 666.

It can be written as a sum of positive squares in only one way, i.e., 19016685801 + 1196053056 = 137901^2 + 34584^2 .

It is not a de Polignac number, because 20212738857 - 2⁴ = 20212738841 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20212738837) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1122929928 + ... + 1122929945.

It is an arithmetic number, because the mean of its divisors is an integer number (4866029727).

Almost surely, 2^20212738857 is an apocalyptic number.

It is an amenable number.

20212738857 is a deficient number, since it is larger than the sum of its proper divisors (8983439505).

20212738857 is a wasteful number, since it uses less digits than its factorization.

20212738857 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2245859879 (or 2245859876 counting only the distinct ones).

The product of its (nonzero) digits is 376320, while the sum is 45.

The spelling of 20212738857 in words is "twenty billion, two hundred twelve million, seven hundred thirty-eight thousand, eight hundred fifty-seven".