1555501661541 has 12 divisors (see below), whose sum is σ = 2324312827980. Its totient is φ = 1001242448640.

The previous prime is 1555501661521. The next prime is 1555501661603. The reversal of 1555501661541 is 1451661055551.

1555501661541 is a `hidden beast` number, since 1 + 5 + 55 + 50 + 1 + 6 + 6 + 1 + 541 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 266311730916 + 1289189930625 = 516054^2 + 1135425^2 .

It is a de Polignac number, because none of the positive numbers 2^k-1555501661541 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1555501661521) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2979887980 + ... + 2979888501.

It is an arithmetic number, because the mean of its divisors is an integer number (193692735665).

Almost surely, 2^{1555501661541} is an apocalyptic number.

It is an amenable number.

1555501661541 is a deficient number, since it is larger than the sum of its proper divisors (768811166439).

1555501661541 is a wasteful number, since it uses less digits than its factorization.

1555501661541 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5959776516 (or 5959776513 counting only the distinct ones).

The product of its (nonzero) digits is 450000, while the sum is 45.

The spelling of 1555501661541 in words is "one trillion, five hundred fifty-five billion, five hundred one million, six hundred sixty-one thousand, five hundred forty-one".