215541131 has 4 divisors (see below), whose sum is σ = 232121232. Its totient is φ = 198961032.

The previous prime is 215541097. The next prime is 215541133. The reversal of 215541131 is 131145512.

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

It is a cyclic number.

It is not a de Polignac number, because 215541131 - 2²⁶ = 148432267 is a prime.

It is a super-2 number, since 2×215541131² = 92915958305518322, 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 = 215541097 and 215541106.

It is not an unprimeable number, because it can be changed into a prime (215541133) 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, 8290031 + ... + 8290056.

It is an arithmetic number, because the mean of its divisors is an integer number (58030308).

Almost surely, 2^215541131 is an apocalyptic number.

215541131 is a deficient number, since it is larger than the sum of its proper divisors (16580101).

215541131 is a wasteful number, since it uses less digits than its factorization.

215541131 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16580100.

The product of its digits is 600, while the sum is 23.

The square root of 215541131 is about 14681.3191164827. The cubic root of 215541131 is about 599.5748200708.

Adding to 215541131 its reverse (131145512), we get a palindrome (346686643).

The spelling of 215541131 in words is "two hundred fifteen million, five hundred forty-one thousand, one hundred thirty-one".