642535406 has 8 divisors (see below), whose sum is σ = 1005707664. Its totient is φ = 307299520.

The previous prime is 642535393. The next prime is 642535441. The reversal of 642535406 is 604535246.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is an unprimeable number.

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, 6984035 + ... + 6984126.

It is an arithmetic number, because the mean of its divisors is an integer number (125713458).

Almost surely, 2^642535406 is an apocalyptic number.

642535406 is a deficient number, since it is larger than the sum of its proper divisors (363172258).

642535406 is a wasteful number, since it uses less digits than its factorization.

642535406 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13968186.

The product of its (nonzero) digits is 86400, while the sum is 35.

The square root of 642535406 is about 25348.2821114173. The cubic root of 642535406 is about 862.9103696143.

The spelling of 642535406 in words is "six hundred forty-two million, five hundred thirty-five thousand, four hundred six".