42378646 has 4 divisors (see below), whose sum is σ = 63567972. Its totient is φ = 21189322.

The previous prime is 42378619. The next prime is 42378649. The reversal of 42378646 is 64687324.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a junction number, because it is equal to n+sod(n) for n = 42378599 and 42378608.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (42378649) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10594660 + ... + 10594663.

It is an arithmetic number, because the mean of its divisors is an integer number (15891993).

Almost surely, 2^42378646 is an apocalyptic number.

42378646 is a deficient number, since it is larger than the sum of its proper divisors (21189326).

42378646 is a wasteful number, since it uses less digits than its factorization.

42378646 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21189325.

The product of its digits is 193536, while the sum is 40.

The square root of 42378646 is about 6509.8883246950. Note that the first 3 decimals coincide. The cubic root of 42378646 is about 348.6441311380.

The spelling of 42378646 in words is "forty-two million, three hundred seventy-eight thousand, six hundred forty-six".