64747440 has 120 divisors (see below), whose sum is σ = 228936240. Its totient is φ = 16353792.

The previous prime is 64747439. The next prime is 64747453. The reversal of 64747440 is 4474746.

64747440 is a `hidden beast` number, since 647 + 4 + 7 + 4 + 4 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (120).

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 = 64747395 and 64747404.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 11314 + ... + 16046.

It is an arithmetic number, because the mean of its divisors is an integer number (1907802).

Almost surely, 2^64747440 is an apocalyptic number.

64747440 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 64747440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (114468120).

64747440 is an abundant number, since it is smaller than the sum of its proper divisors (164188800).

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

64747440 is a wasteful number, since it uses less digits than its factorization.

64747440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4771 (or 4762 counting only the distinct ones).

The product of its (nonzero) digits is 75264, while the sum is 36.

The square root of 64747440 is about 8046.5793974831. The cubic root of 64747440 is about 401.5511437739.

The spelling of 64747440 in words is "sixty-four million, seven hundred forty-seven thousand, four hundred forty".