61281643 has 8 divisors (see below), whose sum is σ = 62451200. Its totient is φ = 60122088.

The previous prime is 61281629. The next prime is 61281667. The reversal of 61281643 is 34618216.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 61281643 - 2¹³ = 61273451 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (61281343) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10498 + ... + 15256.

It is an arithmetic number, because the mean of its divisors is an integer number (7806400).

Almost surely, 2^61281643 is an apocalyptic number.

61281643 is a deficient number, since it is larger than the sum of its proper divisors (1169557).

61281643 is a wasteful number, since it uses less digits than its factorization.

61281643 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5001.

The product of its digits is 6912, while the sum is 31.

The square root of 61281643 is about 7828.2592573317. The cubic root of 61281643 is about 394.2546281102.

Adding to 61281643 its reverse (34618216), we get a palindrome (95899859).

The spelling of 61281643 in words is "sixty-one million, two hundred eighty-one thousand, six hundred forty-three".