642427686 has 40 divisors (see below), whose sum is σ = 1453527504. Its totient is φ = 212058000.

The previous prime is 642427673. The next prime is 642427703. The reversal of 642427686 is 686724246.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 2565 + ... + 35936.

Almost surely, 2^642427686 is an apocalyptic number.

642427686 is an abundant number, since it is smaller than the sum of its proper divisors (811099818).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

642427686 is a wasteful number, since it uses less digits than its factorization.

642427686 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38618 (or 38609 counting only the distinct ones).

The product of its digits is 774144, while the sum is 45.

The square root of 642427686 is about 25346.1572235319. The cubic root of 642427686 is about 862.8621450863.

The spelling of 642427686 in words is "six hundred forty-two million, four hundred twenty-seven thousand, six hundred eighty-six".