156415121 has 4 divisors (see below), whose sum is σ = 156470244. Its totient is φ = 156360000.

The previous prime is 156415117. The next prime is 156415187. The reversal of 156415121 is 121514651.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 100000000 + 56415121 = 10000^2 + 7511^2 .

It is a cyclic number.

It is not a de Polignac number, because 156415121 - 2² = 156415117 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (156418121) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 23060 + ... + 29061.

It is an arithmetic number, because the mean of its divisors is an integer number (39117561).

Almost surely, 2^156415121 is an apocalyptic number.

It is an amenable number.

156415121 is a deficient number, since it is larger than the sum of its proper divisors (55123).

156415121 is an equidigital number, since it uses as much as digits as its factorization.

156415121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55122.

The product of its digits is 1200, while the sum is 26.

The square root of 156415121 is about 12506.6030959649. The cubic root of 156415121 is about 538.7983349991.

Adding to 156415121 its reverse (121514651), we get a palindrome (277929772).

The spelling of 156415121 in words is "one hundred fifty-six million, four hundred fifteen thousand, one hundred twenty-one".