668542534 has 16 divisors (see below), whose sum is σ = 1101229056. Its totient is φ = 301869000.

The previous prime is 668542517. The next prime is 668542577. The reversal of 668542534 is 435245866.

668542534 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 97302 + ... + 103945.

It is an arithmetic number, because the mean of its divisors is an integer number (68826816).

Almost surely, 2^668542534 is an apocalyptic number.

668542534 is a deficient number, since it is larger than the sum of its proper divisors (432686522).

668542534 is a wasteful number, since it uses less digits than its factorization.

668542534 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 201411.

The product of its digits is 691200, while the sum is 43.

The square root of 668542534 is about 25856.1894717687. The cubic root of 668542534 is about 874.3990579580.

The spelling of 668542534 in words is "six hundred sixty-eight million, five hundred forty-two thousand, five hundred thirty-four".