20771573644 has 12 divisors (see below), whose sum is σ = 36351397264. Its totient is φ = 10385460144.

The previous prime is 20771573587. The next prime is 20771573663. The reversal of 20771573644 is 44637517702.

It is a junction number, because it is equal to n+sod(n) for n = 20771573594 and 20771573603.

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, 112897 + ... + 232999.

Almost surely, 2^20771573644 is an apocalyptic number.

It is an amenable number.

20771573644 is a deficient number, since it is larger than the sum of its proper divisors (15579823620).

20771573644 is a wasteful number, since it uses less digits than its factorization.

20771573644 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 163344 (or 163342 counting only the distinct ones).

The product of its (nonzero) digits is 987840, while the sum is 46.

The spelling of 20771573644 in words is "twenty billion, seven hundred seventy-one million, five hundred seventy-three thousand, six hundred forty-four".