641863489 has 4 divisors (see below), whose sum is σ = 641974960. Its totient is φ = 641752020.

The previous prime is 641863471. The next prime is 641863493. The reversal of 641863489 is 984368146.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 984368146 = 2 ⋅492184073.

It is a cyclic number.

It is not a de Polignac number, because 641863489 - 2¹⁷ = 641732417 is a prime.

It is a super-2 number, since 2×641863489² = 823977477022506242, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (641863429) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 46599 + ... + 58780.

It is an arithmetic number, because the mean of its divisors is an integer number (160493740).

Almost surely, 2^641863489 is an apocalyptic number.

It is an amenable number.

641863489 is a deficient number, since it is larger than the sum of its proper divisors (111471).

641863489 is a wasteful number, since it uses less digits than its factorization.

641863489 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 111470.

The product of its digits is 995328, while the sum is 49.

The square root of 641863489 is about 25335.0249457150. The cubic root of 641863489 is about 862.6094749789.

The spelling of 641863489 in words is "six hundred forty-one million, eight hundred sixty-three thousand, four hundred eighty-nine".