647666040 has 64 divisors (see below), whose sum is σ = 2220572160. Its totient is φ = 148037760.

The previous prime is 647666023. The next prime is 647666057. The reversal of 647666040 is 40666746.

647666040 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (647666023) and next prime (647666057).

It is a self number, because there is not a number n which added to its sum of digits gives 647666040.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 384676 + ... + 386355.

It is an arithmetic number, because the mean of its divisors is an integer number (34696440).

Almost surely, 2^647666040 is an apocalyptic number.

647666040 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

647666040 is an abundant number, since it is smaller than the sum of its proper divisors (1572906120).

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

647666040 is a wasteful number, since it uses less digits than its factorization.

647666040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 771052 (or 771048 counting only the distinct ones).

The product of its (nonzero) digits is 145152, while the sum is 39.

The square root of 647666040 is about 25449.2836834360. The cubic root of 647666040 is about 865.2010581000.

The spelling of 647666040 in words is "six hundred forty-seven million, six hundred sixty-six thousand, forty".