215130121 has 4 divisors (see below), whose sum is σ = 227784852. Its totient is φ = 202475392.

The previous prime is 215130119. The next prime is 215130133. The reversal of 215130121 is 121031512.

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 72590400 + 142539721 = 8520^2 + 11939^2 .

It is a cyclic number.

It is not a de Polignac number, because 215130121 - 2¹ = 215130119 is a prime.

It is a super-2 number, since 2×215130121² = 92561937922949282, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 215130095 and 215130104.

It is not an unprimeable number, because it can be changed into a prime (215130151) 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, 6327340 + ... + 6327373.

It is an arithmetic number, because the mean of its divisors is an integer number (56946213).

Almost surely, 2^215130121 is an apocalyptic number.

It is an amenable number.

215130121 is a deficient number, since it is larger than the sum of its proper divisors (12654731).

215130121 is a wasteful number, since it uses less digits than its factorization.

215130121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12654730.

The product of its (nonzero) digits is 60, while the sum is 16.

The square root of 215130121 is about 14667.3147167435. The cubic root of 215130121 is about 599.1934728238.

Adding to 215130121 its reverse (121031512), we get a palindrome (336161633).

The spelling of 215130121 in words is "two hundred fifteen million, one hundred thirty thousand, one hundred twenty-one".