7643840 has 28 divisors (see below), whose sum is σ = 18202656. Its totient is φ = 3057408.

The previous prime is 7643827. The next prime is 7643861. The reversal of 7643840 is 483467.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (32).

It is a junction number, because it is equal to n+sod(n) for n = 7643797 and 7643806.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11624 + ... + 12263.

Almost surely, 2^7643840 is an apocalyptic number.

It is an amenable number.

7643840 is an abundant number, since it is smaller than the sum of its proper divisors (10558816).

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

7643840 is a wasteful number, since it uses less digits than its factorization.

7643840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23904 (or 23894 counting only the distinct ones).

The product of its (nonzero) digits is 16128, while the sum is 32.

The square root of 7643840 is about 2764.7495365765. The cubic root of 7643840 is about 196.9868320710.

The spelling of 7643840 in words is "seven million, six hundred forty-three thousand, eight hundred forty".