15561110061 has 24 divisors (see below), whose sum is σ = 25702632384. Its totient is φ = 8887060800.

The previous prime is 15561110039. The next prime is 15561110063. The reversal of 15561110061 is 16001116551.

15561110061 is a `hidden beast` number, since 1 + 556 + 1 + 1 + 100 + 6 + 1 = 666.

It is not a de Polignac number, because 15561110061 - 2⁹ = 15561109549 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (15561110063) by changing a digit.

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 23 ways as a sum of consecutive naturals, for example, 44890 + ... + 182036.

It is an arithmetic number, because the mean of its divisors is an integer number (1070943016).

Almost surely, 2^15561110061 is an apocalyptic number.

It is an amenable number.

15561110061 is a deficient number, since it is larger than the sum of its proper divisors (10141522323).

15561110061 is a wasteful number, since it uses less digits than its factorization.

15561110061 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 138961 (or 138958 counting only the distinct ones).

The product of its (nonzero) digits is 900, while the sum is 27.

The spelling of 15561110061 in words is "fifteen billion, five hundred sixty-one million, one hundred ten thousand, sixty-one".