646378147 has 4 divisors (see below), whose sum is σ = 649060456. Its totient is φ = 643695840.

The previous prime is 646378133. The next prime is 646378151. The reversal of 646378147 is 741873646.

646378147 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 741873646 = 2 ⋅370936823.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-646378147 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 646378097 and 646378106.

It is not an unprimeable number, because it can be changed into a prime (646378127) 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, 1340793 + ... + 1341274.

It is an arithmetic number, because the mean of its divisors is an integer number (162265114).

Almost surely, 2^646378147 is an apocalyptic number.

646378147 is a deficient number, since it is larger than the sum of its proper divisors (2682309).

646378147 is a wasteful number, since it uses less digits than its factorization.

646378147 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2682308.

The product of its digits is 677376, while the sum is 46.

The square root of 646378147 is about 25423.9679633215. The cubic root of 646378147 is about 864.6271894054.

The spelling of 646378147 in words is "six hundred forty-six million, three hundred seventy-eight thousand, one hundred forty-seven".