202128717172 has 6 divisors (see below), whose sum is σ = 353725255058. Its totient is φ = 101064358584.

The previous prime is 202128717157. The next prime is 202128717173. The reversal of 202128717172 is 271717821202.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 197957365776 + 4171351396 = 444924^2 + 64586^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (202128717173) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25266089643 + ... + 25266089650.

Almost surely, 2^202128717172 is an apocalyptic number.

It is an amenable number.

202128717172 is a deficient number, since it is larger than the sum of its proper divisors (151596537886).

202128717172 is a wasteful number, since it uses less digits than its factorization.

202128717172 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 50532179297 (or 50532179295 counting only the distinct ones).

The product of its (nonzero) digits is 43904, while the sum is 40.

The spelling of 202128717172 in words is "two hundred two billion, one hundred twenty-eight million, seven hundred seventeen thousand, one hundred seventy-two".