7638640 has 20 divisors (see below), whose sum is σ = 17760024. Its totient is φ = 3055424.

The previous prime is 7638619. The next prime is 7638641. The reversal of 7638640 is 468367.

It is a tau number, because it is divible by the number of its divisors (20).

It is a junction number, because it is equal to n+sod(n) for n = 7638596 and 7638605.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7638641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 47662 + ... + 47821.

Almost surely, 2^7638640 is an apocalyptic number.

It is an amenable number.

7638640 is an abundant number, since it is smaller than the sum of its proper divisors (10121384).

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

7638640 is a wasteful number, since it uses less digits than its factorization.

7638640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 95496 (or 95490 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 34.

The square root of 7638640 is about 2763.8089659019. The cubic root of 7638640 is about 196.9421527870.

The spelling of 7638640 in words is "seven million, six hundred thirty-eight thousand, six hundred forty".