3781561305545 has 32 divisors (see below), whose sum is σ = 4681049560704. Its totient is φ = 2931709248000.

The previous prime is 3781561305539. The next prime is 3781561305559. The reversal of 3781561305545 is 5455031651873.

It is a de Polignac number, because none of the positive numbers 2^k-3781561305545 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 4437794 + ... + 5220836.

It is an arithmetic number, because the mean of its divisors is an integer number (146282798772).

Almost surely, 2^{3781561305545} is an apocalyptic number.

It is an amenable number.

3781561305545 is a deficient number, since it is larger than the sum of its proper divisors (899488255159).

3781561305545 is a wasteful number, since it uses less digits than its factorization.

3781561305545 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 783353.

The product of its (nonzero) digits is 7560000, while the sum is 53.

The spelling of 3781561305545 in words is "three trillion, seven hundred eighty-one billion, five hundred sixty-one million, three hundred five thousand, five hundred forty-five".