61638543 has 16 divisors (see below), whose sum is σ = 94466400. Its totient is φ = 39674880.

The previous prime is 61638529. The next prime is 61638547. The reversal of 61638543 is 34583616.

61638543 is a `hidden beast` number, since 616 + 38 + 5 + 4 + 3 = 666.

It is not a de Polignac number, because 61638543 - 2¹⁰ = 61637519 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a junction number, because it is equal to n+sod(n) for n = 61638498 and 61638507.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61638547) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 38578 + ... + 40143.

It is an arithmetic number, because the mean of its divisors is an integer number (5904150).

Almost surely, 2^61638543 is an apocalyptic number.

61638543 is a deficient number, since it is larger than the sum of its proper divisors (32827857).

61638543 is a wasteful number, since it uses less digits than its factorization.

61638543 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 78759 (or 78753 counting only the distinct ones).

The product of its digits is 51840, while the sum is 36.

The square root of 61638543 is about 7851.0217806347. The cubic root of 61638543 is about 395.0185175317.

It can be divided in two parts, 6163 and 8543, that added together give a triangular number (14706 = T₁₇₁).

The spelling of 61638543 in words is "sixty-one million, six hundred thirty-eight thousand, five hundred forty-three".