1646140638 has 8 divisors (see below), whose sum is σ = 3292281288. Its totient is φ = 548713544.

The previous prime is 1646140631. The next prime is 1646140669. The reversal of 1646140638 is 8360416461.

1646140638 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

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

1646140638 is an admirable number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 1646140596 and 1646140605.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1646140631) 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, 137178381 + ... + 137178392.

It is an arithmetic number, because the mean of its divisors is an integer number (411535161).

Almost surely, 2^1646140638 is an apocalyptic number.

1646140638 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

1646140638 is a wasteful number, since it uses less digits than its factorization.

1646140638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 274356778.

The product of its (nonzero) digits is 82944, while the sum is 39.

The square root of 1646140638 is about 40572.6587494584. The cubic root of 1646140638 is about 1180.7437229556.

The spelling of 1646140638 in words is "one billion, six hundred forty-six million, one hundred forty thousand, six hundred thirty-eight".