961644289 has 4 divisors (see below), whose sum is σ = 962506324. Its totient is φ = 960782256.

The previous prime is 961644269. The next prime is 961644301. The reversal of 961644289 is 982446169.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 982446169 = 89 ⋅11038721.

It can be written as a sum of positive squares in 2 ways, for example, as 47610000 + 914034289 = 6900^2 + 30233^2 .

It is a cyclic number.

It is not a de Polignac number, because 961644289 - 2⁷ = 961644161 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (961644209) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 429342 + ... + 431575.

It is an arithmetic number, because the mean of its divisors is an integer number (240626581).

Almost surely, 2^961644289 is an apocalyptic number.

It is an amenable number.

961644289 is a deficient number, since it is larger than the sum of its proper divisors (862035).

961644289 is a wasteful number, since it uses less digits than its factorization.

961644289 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 862034.

The product of its digits is 746496, while the sum is 49.

The square root of 961644289 is about 31010.3900168960. The cubic root of 961644289 is about 987.0477258927.

The spelling of 961644289 in words is "nine hundred sixty-one million, six hundred forty-four thousand, two hundred eighty-nine".