171556225656 has 32 divisors (see below), whose sum is σ = 430416882000. Its totient is φ = 56981899520.

The previous prime is 171556225553. The next prime is 171556225657. The reversal of 171556225656 is 656522655171.

It is a super-2 number, since 2×171556225656² (a number of 23 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 171556225599 and 171556225608.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (171556225657) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12712431 + ... + 12725918.

Almost surely, 2^171556225656 is an apocalyptic number.

It is an amenable number.

171556225656 is an abundant number, since it is smaller than the sum of its proper divisors (258860656344).

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

171556225656 is a wasteful number, since it uses less digits than its factorization.

171556225656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25438639 (or 25438635 counting only the distinct ones).

The product of its digits is 3780000, while the sum is 51.

It can be divided in two parts, 17155 and 6225656, that added together give a triangular number (6242811 = T₃₅₃₃).

The spelling of 171556225656 in words is "one hundred seventy-one billion, five hundred fifty-six million, two hundred twenty-five thousand, six hundred fifty-six".