647735440 has 40 divisors (see below), whose sum is σ = 1642894848. Its totient is φ = 235539840.

The previous prime is 647735437. The next prime is 647735447. The reversal of 647735440 is 44537746.

It is a tau number, because it is divible by the number of its divisors (40).

It is a super-2 number, since 2×647735440² = 839122400463987200, which contains 22 as substring.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (40).

It is a junction number, because it is equal to n+sod(n) for n = 647735393 and 647735402.

It is not an unprimeable number, because it can be changed into a prime (647735447) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 367152 + ... + 368911.

Almost surely, 2^647735440 is an apocalyptic number.

It is an amenable number.

647735440 is an abundant number, since it is smaller than the sum of its proper divisors (995159408).

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

647735440 is a wasteful number, since it uses less digits than its factorization.

647735440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 736087 (or 736081 counting only the distinct ones).

The product of its (nonzero) digits is 282240, while the sum is 40.

The square root of 647735440 is about 25450.6471430492. The cubic root of 647735440 is about 865.2319602446.

The spelling of 647735440 in words is "six hundred forty-seven million, seven hundred thirty-five thousand, four hundred forty".