667951 has 4 divisors (see below), whose sum is σ = 669600. Its totient is φ = 666304.

The previous prime is 667949. The next prime is 667963. The reversal of 667951 is 159766.

667951 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 667951 - 2¹ = 667949 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (667921) 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, 255 + ... + 1183.

It is an arithmetic number, because the mean of its divisors is an integer number (167400).

2⁶⁶⁷⁹⁵¹ is an apocalyptic number.

667951 is the 366-th centered decagonal number.

667951 is a deficient number, since it is larger than the sum of its proper divisors (1649).

667951 is an equidigital number, since it uses as much as digits as its factorization.

667951 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1648.

The product of its digits is 11340, while the sum is 34.

The square root of 667951 is about 817.2826928303. The cubic root of 667951 is about 87.4141089131.

The spelling of 667951 in words is "six hundred sixty-seven thousand, nine hundred fifty-one".