159169556421 has 24 divisors (see below), whose sum is σ = 232233281280. Its totient is φ = 105046805376.

The previous prime is 159169556353. The next prime is 159169556453. The reversal of 159169556421 is 124655961951.

159169556421 is a `hidden beast` number, since 1 + 5 + 9 + 1 + 69 + 556 + 4 + 21 = 666.

It is not a de Polignac number, because 159169556421 - 2¹⁹ = 159169032133 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (159169554421) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 137725 + ... + 580781.

It is an arithmetic number, because the mean of its divisors is an integer number (9676386720).

Almost surely, 2^159169556421 is an apocalyptic number.

It is an amenable number.

159169556421 is a deficient number, since it is larger than the sum of its proper divisors (73063724859).

159169556421 is a wasteful number, since it uses less digits than its factorization.

159169556421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 443465 (or 443462 counting only the distinct ones).

The product of its digits is 2916000, while the sum is 54.

The spelling of 159169556421 in words is "one hundred fifty-nine billion, one hundred sixty-nine million, five hundred fifty-six thousand, four hundred twenty-one".