3531440640 has 640 divisors, whose sum is σ = 14431076352. Its totient is φ = 716636160.

The previous prime is 3531440639. The next prime is 3531440641. The reversal of 3531440640 is 460441353.

It is an interprime number because it is at equal distance from previous prime (3531440639) and next prime (3531440641).

It is a tau number, because it is divible by the number of its divisors (640).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 3531440598 and 3531440607.

It is not an unprimeable number, because it can be changed into a prime (3531440641) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 21665199 + ... + 21665361.

Almost surely, 2^3531440640 is an apocalyptic number.

3531440640 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 3531440640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (7215538176).

3531440640 is an abundant number, since it is smaller than the sum of its proper divisors (10899635712).

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

3531440640 is a wasteful number, since it uses less digits than its factorization.

3531440640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 240 (or 224 counting only the distinct ones).

The product of its (nonzero) digits is 17280, while the sum is 30.

The square root of 3531440640 is about 59425.9256553905. The cubic root of 3531440640 is about 1522.8272403060.

Adding to 3531440640 its reverse (460441353), we get a palindrome (3991881993).

The spelling of 3531440640 in words is "three billion, five hundred thirty-one million, four hundred forty thousand, six hundred forty".