61643 has 2 divisors, whose sum is σ = 61644. Its totient is φ = 61642.

The previous prime is 61637. The next prime is 61651. The reversal of 61643 is 34616.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 61643 - 2⁴ = 61627 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (61603) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30821 + 30822.

It is an arithmetic number, because the mean of its divisors is an integer number (30822).

2⁶¹⁶⁴³ is an apocalyptic number.

61643 is a deficient number, since it is larger than the sum of its proper divisors (1).

61643 is an equidigital number, since it uses as much as digits as its factorization.

61643 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 432, while the sum is 20.

The square root of 61643 is about 248.2800837764. The cubic root of 61643 is about 39.5028038388.

The spelling of 61643 in words is "sixty-one thousand, six hundred forty-three".