3644353440 has 864 divisors, whose sum is σ = 16234480080. Its totient is φ = 736985088.

The previous prime is 3644353423. The next prime is 3644353451. The reversal of 3644353440 is 443534463.

3644353440 is a `hidden beast` number, since 3 + 644 + 3 + 5 + 3 + 4 + 4 + 0 = 666.

It can be written as a sum of positive squares in 8 ways, for example, as 1078728336 + 2565625104 = 32844^2 + 50652^2 .

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 = 3644353395 and 3644353404.

It is an unprimeable number.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 26601052 + ... + 26601188.

Almost surely, 2^3644353440 is an apocalyptic number.

3644353440 is a gapful number since it is divisible by the number (30) 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 3644353440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (8117240040).

3644353440 is an abundant number, since it is smaller than the sum of its proper divisors (12590126640).

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

3644353440 is a wasteful number, since it uses less digits than its factorization.

3644353440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 214 (or 196 counting only the distinct ones).

The product of its (nonzero) digits is 207360, while the sum is 36.

The square root of 3644353440 is about 60368.4805175681. The cubic root of 3644353440 is about 1538.8873505748.

The spelling of 3644353440 in words is "three billion, six hundred forty-four million, three hundred fifty-three thousand, four hundred forty".