156400121 has 2 divisors, whose sum is σ = 156400122. Its totient is φ = 156400120.

The previous prime is 156400063. The next prime is 156400129. The reversal of 156400121 is 121004651.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 155276521 + 1123600 = 12461^2 + 1060^2 .

It is an emirp because it is prime and its reverse (121004651) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 156400121 - 2¹⁰ = 156399097 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 156400093 and 156400102.

It is not a weakly prime, because it can be changed into another prime (156400129) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 78200060 + 78200061.

It is an arithmetic number, because the mean of its divisors is an integer number (78200061).

Almost surely, 2^156400121 is an apocalyptic number.

It is an amenable number.

156400121 is a deficient number, since it is larger than the sum of its proper divisors (1).

156400121 is an equidigital number, since it uses as much as digits as its factorization.

156400121 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 240, while the sum is 20.

The square root of 156400121 is about 12506.0033983683. The cubic root of 156400121 is about 538.7811111029.

Adding to 156400121 its reverse (121004651), we get a palindrome (277404772).

The spelling of 156400121 in words is "one hundred fifty-six million, four hundred thousand, one hundred twenty-one".