668479 has 16 divisors (see below), whose sum is σ = 820800. Its totient is φ = 532224.

The previous prime is 668471. The next prime is 668509. The reversal of 668479 is 974866.

668479 = T₃₀₂ + T₃₀₃ + ... + T₃₁₅.

It is not a de Polignac number, because 668479 - 2³ = 668471 is a prime.

It is a Duffinian number.

Its product of digits (72576) is a multiple of the sum of its prime divisors (162).

668479 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (668471) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7467 + ... + 7555.

It is an arithmetic number, because the mean of its divisors is an integer number (51300).

2⁶⁶⁸⁴⁷⁹ is an apocalyptic number.

668479 is a deficient number, since it is larger than the sum of its proper divisors (152321).

668479 is a wasteful number, since it uses less digits than its factorization.

668479 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 162.

The product of its digits is 72576, while the sum is 40.

The square root of 668479 is about 817.6056506654. The cubic root of 668479 is about 87.4371357985.

The spelling of 668479 in words is "six hundred sixty-eight thousand, four hundred seventy-nine".