642404078 has 8 divisors (see below), whose sum is σ = 963991800. Its totient is φ = 321073480.

The previous prime is 642404071. The next prime is 642404083. The reversal of 642404078 is 870404246.

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

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (642404071) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 57908 + ... + 68103.

It is an arithmetic number, because the mean of its divisors is an integer number (120498975).

Almost surely, 2^642404078 is an apocalyptic number.

642404078 is a deficient number, since it is larger than the sum of its proper divisors (321587722).

642404078 is a wasteful number, since it uses less digits than its factorization.

642404078 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 128562.

The product of its (nonzero) digits is 43008, while the sum is 35.

The square root of 642404078 is about 25345.6915076310. The cubic root of 642404078 is about 862.8515754406.

The spelling of 642404078 in words is "six hundred forty-two million, four hundred four thousand, seventy-eight".