131511213 has 6 divisors (see below), whose sum is σ = 189960654. Its totient is φ = 87674136.

The previous prime is 131511197. The next prime is 131511223. The reversal of 131511213 is 312115131.

131511213 is a `hidden beast` number, since 131 + 511 + 21 + 3 = 666.

It can be written as a sum of positive squares in only one way, i.e., 126832644 + 4678569 = 11262^2 + 2163^2 .

It is not a de Polignac number, because 131511213 - 2⁴ = 131511197 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (131511223) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 7306170 + ... + 7306187.

It is an arithmetic number, because the mean of its divisors is an integer number (31660109).

Almost surely, 2^131511213 is an apocalyptic number.

It is an amenable number.

131511213 is a deficient number, since it is larger than the sum of its proper divisors (58449441).

131511213 is a wasteful number, since it uses less digits than its factorization.

131511213 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14612363 (or 14612360 counting only the distinct ones).

The product of its digits is 90, while the sum is 18.

The square root of 131511213 is about 11467.8338407914. The cubic root of 131511213 is about 508.5350927014.

Adding to 131511213 its reverse (312115131), we get a palindrome (443626344).

The spelling of 131511213 in words is "one hundred thirty-one million, five hundred eleven thousand, two hundred thirteen".