216435131 has 4 divisors (see below), whose sum is σ = 236111064. Its totient is φ = 196759200.

The previous prime is 216435127. The next prime is 216435133. The reversal of 216435131 is 131534612.

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

It is not a de Polignac number, because 216435131 - 2² = 216435127 is a prime.

It is a super-2 number, since 2×216435131² = 93688331861974322, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 216435131.

It is not an unprimeable number, because it can be changed into a prime (216435133) 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, 9837950 + ... + 9837971.

It is an arithmetic number, because the mean of its divisors is an integer number (59027766).

Almost surely, 2^216435131 is an apocalyptic number.

216435131 is a deficient number, since it is larger than the sum of its proper divisors (19675933).

216435131 is a wasteful number, since it uses less digits than its factorization.

216435131 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19675932.

The product of its digits is 2160, while the sum is 26.

The square root of 216435131 is about 14711.7344660648. The cubic root of 216435131 is about 600.4026288303.

Adding to 216435131 its reverse (131534612), we get a palindrome (347969743).

The spelling of 216435131 in words is "two hundred sixteen million, four hundred thirty-five thousand, one hundred thirty-one".