646580340 has 96 divisors (see below), whose sum is σ = 2298965760. Its totient is φ = 147788928.

The previous prime is 646580321. The next prime is 646580353. The reversal of 646580340 is 43085646.

646580340 is a `hidden beast` number, since 6 + 46 + 580 + 34 + 0 = 666.

It is a super-2 number, since 2×646580340² = 836132272149031200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 646580295 and 646580304.

It is a congruent number.

It is an unprimeable number.

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 31 ways as a sum of consecutive naturals, for example, 81747 + ... + 89306.

It is an arithmetic number, because the mean of its divisors is an integer number (23947560).

Almost surely, 2^646580340 is an apocalyptic number.

646580340 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

646580340 is an abundant number, since it is smaller than the sum of its proper divisors (1652385420).

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

646580340 is a wasteful number, since it uses less digits than its factorization.

646580340 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 171078 (or 171070 counting only the distinct ones).

The product of its (nonzero) digits is 69120, while the sum is 36.

The square root of 646580340 is about 25427.9440773335. The cubic root of 646580340 is about 864.7173344393.

The spelling of 646580340 in words is "six hundred forty-six million, five hundred eighty thousand, three hundred forty".