647977440 has 192 divisors, whose sum is σ = 2357994240. Its totient is φ = 147824640.

The previous prime is 647977439. The next prime is 647977507. The reversal of 647977440 is 44779746.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a self number, because there is not a number n which added to its sum of digits gives 647977440.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 86151 + ... + 93369.

It is an arithmetic number, because the mean of its divisors is an integer number (12281220).

Almost surely, 2^647977440 is an apocalyptic number.

647977440 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 647977440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1178997120).

647977440 is an abundant number, since it is smaller than the sum of its proper divisors (1710016800).

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

647977440 is a wasteful number, since it uses less digits than its factorization.

647977440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7265 (or 7257 counting only the distinct ones).

The product of its (nonzero) digits is 1185408, while the sum is 48.

The square root of 647977440 is about 25455.4009986093. The cubic root of 647977440 is about 865.3396997376.

The spelling of 647977440 in words is "six hundred forty-seven million, nine hundred seventy-seven thousand, four hundred forty".