667440031 has 4 divisors (see below), whose sum is σ = 668049552. Its totient is φ = 666830512.

The previous prime is 667440029. The next prime is 667440071. The reversal of 667440031 is 130044766.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 130044766 = 2 ⋅65022383.

It is a cyclic number.

It is not a de Polignac number, because 667440031 - 2¹ = 667440029 is a prime.

It is a super-2 number, since 2×667440031² = 890952389962561922, 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 = 667439975 and 667440002.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (667440001) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 303115 + ... + 305308.

It is an arithmetic number, because the mean of its divisors is an integer number (167012388).

Almost surely, 2^667440031 is an apocalyptic number.

667440031 is a deficient number, since it is larger than the sum of its proper divisors (609521).

667440031 is a wasteful number, since it uses less digits than its factorization.

667440031 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 609520.

The product of its (nonzero) digits is 12096, while the sum is 31.

The square root of 667440031 is about 25834.8607698977. The cubic root of 667440031 is about 873.9181321868.

Adding to 667440031 its reverse (130044766), we get a palindrome (797484797).

The spelling of 667440031 in words is "six hundred sixty-seven million, four hundred forty thousand, thirty-one".