3521782440 has 144 divisors (see below), whose sum is σ = 12581068500. Its totient is φ = 853754880.

The previous prime is 3521782409. The next prime is 3521782469. The reversal of 3521782440 is 442871253.

It is a happy number.

3521782440 is a `hidden beast` number, since 3 + 521 + 78 + 24 + 40 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 3520523556 + 1258884 = 59334^2 + 1122^2 .

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 = 3521782395 and 3521782404.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 3136 + ... + 83984.

Almost surely, 2^3521782440 is an apocalyptic number.

3521782440 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 3521782440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (6290534250).

3521782440 is an abundant number, since it is smaller than the sum of its proper divisors (9059286060).

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

3521782440 is a wasteful number, since it uses less digits than its factorization.

3521782440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 80888 (or 80870 counting only the distinct ones).

The product of its (nonzero) digits is 53760, while the sum is 36.

The square root of 3521782440 is about 59344.6075056529. The cubic root of 3521782440 is about 1521.4377036510.

The spelling of 3521782440 in words is "three billion, five hundred twenty-one million, seven hundred eighty-two thousand, four hundred forty".