647740 has 24 divisors (see below), whose sum is σ = 1375920. Its totient is φ = 256128.

The previous prime is 647723. The next prime is 647741. The reversal of 647740 is 47746.

647740 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a hoax number, since the sum of its digits (28) coincides with the sum of the digits of its distinct prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 647699 and 647708.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (647741) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2664 + ... + 2896.

It is an arithmetic number, because the mean of its divisors is an integer number (57330).

2⁶⁴⁷⁷⁴⁰ is an apocalyptic number.

It is an amenable number.

647740 is an abundant number, since it is smaller than the sum of its proper divisors (728180).

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

647740 is a wasteful number, since it uses less digits than its factorization.

647740 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 381 (or 379 counting only the distinct ones).

The product of its (nonzero) digits is 4704, while the sum is 28.

The square root of 647740 is about 804.8229618991. The cubic root of 647740 is about 86.5233990625.

The spelling of 647740 in words is "six hundred forty-seven thousand, seven hundred forty".