1361561611554 has 24 divisors (see below), whose sum is σ = 3022002602892. Its totient is φ = 442784263680.

The previous prime is 1361561611549. The next prime is 1361561611567. The reversal of 1361561611554 is 4551161651631.

1361561611554 is a `hidden beast` number, since 1 + 3 + 6 + 15 + 616 + 1 + 15 + 5 + 4 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 1151318270025 + 210243341529 = 1072995^2 + 458523^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 922466479 + ... + 922467954.

Almost surely, 2^{1361561611554} is an apocalyptic number.

1361561611554 is an abundant number, since it is smaller than the sum of its proper divisors (1660440991338).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1361561611554 is a wasteful number, since it uses less digits than its factorization.

1361561611554 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1844934482 (or 1844934479 counting only the distinct ones).

The product of its digits is 324000, while the sum is 45.

The spelling of 1361561611554 in words is "one trillion, three hundred sixty-one billion, five hundred sixty-one million, six hundred eleven thousand, five hundred fifty-four".