646782044 has 48 divisors (see below), whose sum is σ = 1174376448. Its totient is φ = 311568768.

The previous prime is 646782043. The next prime is 646782077. The reversal of 646782044 is 440287646.

It is a junction number, because it is equal to n+sod(n) for n = 646781992 and 646782010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (646782043) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3967907 + ... + 3968069.

It is an arithmetic number, because the mean of its divisors is an integer number (24466176).

Almost surely, 2^646782044 is an apocalyptic number.

It is an amenable number.

646782044 is a deficient number, since it is larger than the sum of its proper divisors (527594404).

646782044 is a wasteful number, since it uses less digits than its factorization.

646782044 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 474 (or 472 counting only the distinct ones).

The product of its (nonzero) digits is 258048, while the sum is 41.

The square root of 646782044 is about 25431.9099558016. The cubic root of 646782044 is about 864.8072427363.

The spelling of 646782044 in words is "six hundred forty-six million, seven hundred eighty-two thousand, forty-four".