171220156928 has 30 divisors (see below), whose sum is σ = 342124608111. Its totient is φ = 85605396992.

The previous prime is 171220156907. The next prime is 171220156937. The reversal of 171220156928 is 829651022171.

It is a powerful number, because all its prime factors have an exponent greater than 1 and also an Achilles number because it is not a perfect power.

It can be written as a sum of positive squares in only one way, i.e., 85610078464 + 85610078464 = 292592^2 + 292592^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=292592.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 9353801 + ... + 9372087.

Almost surely, 2^171220156928 is an apocalyptic number.

It is an amenable number.

171220156928 is a deficient number, since it is larger than the sum of its proper divisors (170904451183).

171220156928 is an frugal number, since it uses more digits than its factorization.

171220156928 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36592 (or 18289 counting only the distinct ones).

The product of its (nonzero) digits is 120960, while the sum is 44.

The spelling of 171220156928 in words is "one hundred seventy-one billion, two hundred twenty million, one hundred fifty-six thousand, nine hundred twenty-eight".