3561221376 has 432 divisors, whose sum is σ = 11785213440. Its totient is φ = 1067489280.

The previous prime is 3561221341. The next prime is 3561221413. The reversal of 3561221376 is 6731221653.

3561221376 is a `hidden beast` number, since 3 + 5 + 61 + 221 + 376 = 666.

It is a tau number, because it is divible by the number of its divisors (432).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 3561221376.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 27184831 + ... + 27184961.

Almost surely, 2^3561221376 is an apocalyptic number.

3561221376 is a gapful number since it is divisible by the number (36) 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 3561221376, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (5892606720).

3561221376 is an abundant number, since it is smaller than the sum of its proper divisors (8223992064).

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

3561221376 is a wasteful number, since it uses less digits than its factorization.

3561221376 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 204 (or 178 counting only the distinct ones).

The product of its digits is 45360, while the sum is 36.

The square root of 3561221376 is about 59675.9698371128. The cubic root of 3561221376 is about 1527.0959446587.

The spelling of 3561221376 in words is "three billion, five hundred sixty-one million, two hundred twenty-one thousand, three hundred seventy-six".