131218733 has 4 divisors (see below), whose sum is σ = 138937500. Its totient is φ = 123499968.

The previous prime is 131218727. The next prime is 131218739. The reversal of 131218733 is 337812131.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 337812131 = 3389 ⋅99679.

It is an interprime number because it is at equal distance from previous prime (131218727) and next prime (131218739).

It can be written as a sum of positive squares in 2 ways, for example, as 100060009 + 31158724 = 10003^2 + 5582^2 .

It is not a de Polignac number, because 131218733 - 2¹⁴ = 131202349 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 131218696 and 131218705.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (131218739) 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, 3859358 + ... + 3859391.

It is an arithmetic number, because the mean of its divisors is an integer number (34734375).

Almost surely, 2^131218733 is an apocalyptic number.

It is an amenable number.

131218733 is a deficient number, since it is larger than the sum of its proper divisors (7718767).

131218733 is an equidigital number, since it uses as much as digits as its factorization.

131218733 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7718766.

The product of its digits is 3024, while the sum is 29.

The square root of 131218733 is about 11455.0745523545. The cubic root of 131218733 is about 508.1578200725.

The spelling of 131218733 in words is "one hundred thirty-one million, two hundred eighteen thousand, seven hundred thirty-three".