651426640 has 20 divisors (see below), whose sum is σ = 1514567124. Its totient is φ = 260570624.

The previous prime is 651426637. The next prime is 651426641. The reversal of 651426640 is 46624156.

It can be written as a sum of positive squares in 2 ways, for example, as 187799616 + 463627024 = 13704^2 + 21532^2 .

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 = 651426596 and 651426605.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (651426641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4071337 + ... + 4071496.

Almost surely, 2^651426640 is an apocalyptic number.

It is an amenable number.

651426640 is an abundant number, since it is smaller than the sum of its proper divisors (863140484).

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

651426640 is a wasteful number, since it uses less digits than its factorization.

651426640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8142846 (or 8142840 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 34.

The square root of 651426640 is about 25523.0609449572. The cubic root of 651426640 is about 866.8723916618.

The spelling of 651426640 in words is "six hundred fifty-one million, four hundred twenty-six thousand, six hundred forty".