3561952221 has 24 divisors (see below), whose sum is σ = 5214736800. Its totient is φ = 2342553696.

The previous prime is 3561952169. The next prime is 3561952259. The reversal of 3561952221 is 1222591653.

It is a happy number.

3561952221 is a `hidden beast` number, since 3 + 561 + 95 + 2 + 2 + 2 + 1 = 666.

It is not a de Polignac number, because 3561952221 - 2⁶ = 3561952157 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3561952271) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 562330 + ... + 568628.

It is an arithmetic number, because the mean of its divisors is an integer number (217280700).

Almost surely, 2^3561952221 is an apocalyptic number.

It is an amenable number.

3561952221 is a deficient number, since it is larger than the sum of its proper divisors (1652784579).

3561952221 is a wasteful number, since it uses less digits than its factorization.

3561952221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7145 (or 7142 counting only the distinct ones).

The product of its digits is 32400, while the sum is 36.

The square root of 3561952221 is about 59682.0929676566. The cubic root of 3561952221 is about 1527.2004026502.

The spelling of 3561952221 in words is "three billion, five hundred sixty-one million, nine hundred fifty-two thousand, two hundred twenty-one".