3216306561 has 16 divisors (see below), whose sum is σ = 4725690816. Its totient is φ = 1933235136.

The previous prime is 3216306481. The next prime is 3216306571. The reversal of 3216306561 is 1656036123.

It is not a de Polignac number, because 3216306561 - 2⁷ = 3216306433 is a prime.

It is not an unprimeable number, because it can be changed into a prime (3216306571) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 957270 + ... + 960623.

It is an arithmetic number, because the mean of its divisors is an integer number (295355676).

Almost surely, 2^3216306561 is an apocalyptic number.

It is an amenable number.

3216306561 is a deficient number, since it is larger than the sum of its proper divisors (1509384255).

3216306561 is a wasteful number, since it uses less digits than its factorization.

3216306561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1917952.

The product of its (nonzero) digits is 19440, while the sum is 33.

The square root of 3216306561 is about 56712.4903438387. The cubic root of 3216306561 is about 1476.1114382376. Note that the first 3 decimals are identical.

The spelling of 3216306561 in words is "three billion, two hundred sixteen million, three hundred six thousand, five hundred sixty-one".