61543566 has 24 divisors (see below), whose sum is σ = 152393904. Its totient is φ = 17583840.

The previous prime is 61543499. The next prime is 61543567. The reversal of 61543566 is 66534516.

61543566 is a `hidden beast` number, since 61 + 543 + 56 + 6 = 666.

61543566 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×61543566² = 7575221031992712, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 61543566.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61543567) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 244095 + ... + 244346.

It is an arithmetic number, because the mean of its divisors is an integer number (6349746).

Almost surely, 2^61543566 is an apocalyptic number.

61543566 is an abundant number, since it is smaller than the sum of its proper divisors (90850338).

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

61543566 is a wasteful number, since it uses less digits than its factorization.

61543566 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 488456 (or 488453 counting only the distinct ones).

The product of its digits is 64800, while the sum is 36.

The square root of 61543566 is about 7844.9707456434. The cubic root of 61543566 is about 394.8155224663.

The spelling of 61543566 in words is "sixty-one million, five hundred forty-three thousand, five hundred sixty-six".