156120321 has 24 divisors (see below), whose sum is σ = 254894880. Its totient is φ = 84514752.

The previous prime is 156120319. The next prime is 156120347. The reversal of 156120321 is 123021651.

It is not a de Polignac number, because 156120321 - 2¹ = 156120319 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is not an unprimeable number, because it can be changed into a prime (156120301) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 25156 + ... + 30741.

It is an arithmetic number, because the mean of its divisors is an integer number (10620620).

Almost surely, 2^156120321 is an apocalyptic number.

It is an amenable number.

156120321 is a deficient number, since it is larger than the sum of its proper divisors (98774559).

156120321 is a wasteful number, since it uses less digits than its factorization.

156120321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55933 (or 55926 counting only the distinct ones).

The product of its (nonzero) digits is 360, while the sum is 21.

The square root of 156120321 is about 12494.8117632880. The cubic root of 156120321 is about 538.4596259676.

Adding to 156120321 its reverse (123021651), we get a palindrome (279141972).

The spelling of 156120321 in words is "one hundred fifty-six million, one hundred twenty thousand, three hundred twenty-one".