159056721 has 6 divisors (see below), whose sum is σ = 229748610. Its totient is φ = 106037808.

The previous prime is 159056717. The next prime is 159056731. The reversal of 159056721 is 127650951.

159056721 is a `hidden beast` number, since 1 + 5 + 90 + 567 + 2 + 1 = 666.

It can be written as a sum of positive squares in only one way, i.e., 87890625 + 71166096 = 9375^2 + 8436^2 .

It is not a de Polignac number, because 159056721 - 2² = 159056717 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (159056701) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 8836476 + ... + 8836493.

It is an arithmetic number, because the mean of its divisors is an integer number (38291435).

Almost surely, 2^159056721 is an apocalyptic number.

It is an amenable number.

159056721 is a deficient number, since it is larger than the sum of its proper divisors (70691889).

159056721 is a wasteful number, since it uses less digits than its factorization.

159056721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17672975 (or 17672972 counting only the distinct ones).

The product of its (nonzero) digits is 18900, while the sum is 36.

The square root of 159056721 is about 12611.7691463173. The cubic root of 159056721 is about 541.8145644056.

It can be divided in two parts, 1590 and 56721, that added together give a triangular number (58311 = T₃₄₁).

The spelling of 159056721 in words is "one hundred fifty-nine million, fifty-six thousand, seven hundred twenty-one".