3561661304251 has 16 divisors (see below), whose sum is σ = 3662693290080. Its totient is φ = 3461481031680.

The previous prime is 3561661304239. The next prime is 3561661304303. The reversal of 3561661304251 is 1524031661653.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-3561661304251 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (43).

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 3561661304198 and 3561661304207.

It is not an unprimeable number, because it can be changed into a prime (3561661304231) 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, 12219015 + ... + 12507103.

It is an arithmetic number, because the mean of its divisors is an integer number (228918330630).

Almost surely, 2^{3561661304251} is an apocalyptic number.

3561661304251 is a deficient number, since it is larger than the sum of its proper divisors (101031985829).

3561661304251 is a wasteful number, since it uses less digits than its factorization.

3561661304251 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 289566.

The product of its (nonzero) digits is 388800, while the sum is 43.

The spelling of 3561661304251 in words is "three trillion, five hundred sixty-one billion, six hundred sixty-one million, three hundred four thousand, two hundred fifty-one".