216494131 has 4 divisors (see below), whose sum is σ = 247421872. Its totient is φ = 185566392.

The previous prime is 216494119. The next prime is 216494143. The reversal of 216494131 is 131494612.

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

It is an interprime number because it is at equal distance from previous prime (216494119) and next prime (216494143).

It is a cyclic number.

It is not a de Polignac number, because 216494131 - 2²⁵ = 182939699 is a prime.

It is a super-2 number, since 2×216494131² = 93739417514890322, 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 = 216494093 and 216494102.

It is not an unprimeable number, because it can be changed into a prime (216494171) 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, 15463860 + ... + 15463873.

It is an arithmetic number, because the mean of its divisors is an integer number (61855468).

Almost surely, 2^216494131 is an apocalyptic number.

216494131 is a deficient number, since it is larger than the sum of its proper divisors (30927741).

216494131 is an equidigital number, since it uses as much as digits as its factorization.

216494131 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30927740.

The product of its digits is 5184, while the sum is 31.

The square root of 216494131 is about 14713.7395314719. The cubic root of 216494131 is about 600.4571802589.

The spelling of 216494131 in words is "two hundred sixteen million, four hundred ninety-four thousand, one hundred thirty-one".