668031457 has 2 divisors, whose sum is σ = 668031458. Its totient is φ = 668031456.

The previous prime is 668031391. The next prime is 668031577. The reversal of 668031457 is 754130866.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 539911696 + 128119761 = 23236^2 + 11319^2 .

It is a cyclic number.

It is not a de Polignac number, because 668031457 - 2¹¹ = 668029409 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (668031857) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 334015728 + 334015729.

It is an arithmetic number, because the mean of its divisors is an integer number (334015729).

Almost surely, 2^668031457 is an apocalyptic number.

It is an amenable number.

668031457 is a deficient number, since it is larger than the sum of its proper divisors (1).

668031457 is an equidigital number, since it uses as much as digits as its factorization.

668031457 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 120960, while the sum is 40.

The square root of 668031457 is about 25846.3045134116. The cubic root of 668031457 is about 874.1761854909.

The spelling of 668031457 in words is "six hundred sixty-eight million, thirty-one thousand, four hundred fifty-seven".