1611561605563 has 32 divisors (see below), whose sum is σ = 2054187596160. Its totient is φ = 1229714196480.

The previous prime is 1611561605561. The next prime is 1611561605569. The reversal of 1611561605563 is 3655061651161.

It is not a de Polignac number, because 1611561605563 - 2¹ = 1611561605561 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1611561605561) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1978381 + ... + 2671537.

It is an arithmetic number, because the mean of its divisors is an integer number (64193362380).

Almost surely, 2^{1611561605563} is an apocalyptic number.

1611561605563 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

1611561605563 is a deficient number, since it is larger than the sum of its proper divisors (442625990597).

1611561605563 is a wasteful number, since it uses less digits than its factorization.

1611561605563 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 694087.

The product of its (nonzero) digits is 486000, while the sum is 46.

The spelling of 1611561605563 in words is "one trillion, six hundred eleven billion, five hundred sixty-one million, six hundred five thousand, five hundred sixty-three".