156201121 has 2 divisors, whose sum is σ = 156201122. Its totient is φ = 156201120.

The previous prime is 156201113. The next prime is 156201139. The reversal of 156201121 is 121102651.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 143520400 + 12680721 = 11980^2 + 3561^2 .

It is a cyclic number.

It is not a de Polignac number, because 156201121 - 2³ = 156201113 is a prime.

It is a super-3 number, since 3×156201121³ (a number of 26 digits) contains 333 as substring.

It is not a weakly prime, because it can be changed into another prime (156201191) 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 as a sum of consecutive naturals, namely, 78100560 + 78100561.

It is an arithmetic number, because the mean of its divisors is an integer number (78100561).

Almost surely, 2^156201121 is an apocalyptic number.

It is an amenable number.

156201121 is a deficient number, since it is larger than the sum of its proper divisors (1).

156201121 is an equidigital number, since it uses as much as digits as its factorization.

156201121 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 120, while the sum is 19.

The square root of 156201121 is about 12498.0446870701. The cubic root of 156201121 is about 538.5525031234.

Adding to 156201121 its reverse (121102651), we get a palindrome (277303772).

The spelling of 156201121 in words is "one hundred fifty-six million, two hundred one thousand, one hundred twenty-one".