6440961 has 4 divisors (see below), whose sum is σ = 8587952. Its totient is φ = 4293972.

The previous prime is 6440953. The next prime is 6440969. The reversal of 6440961 is 1690446.

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.

It is an interprime number because it is at equal distance from previous prime (6440953) and next prime (6440969).

It is not a de Polignac number, because 6440961 - 2³ = 6440953 is a prime.

It is a D-number.

It is a Duffinian number.

It is a Curzon number.

6440961 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (6440969) 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, 1073491 + ... + 1073496.

It is an arithmetic number, because the mean of its divisors is an integer number (2146988).

Almost surely, 2^6440961 is an apocalyptic number.

It is an amenable number.

6440961 is a deficient number, since it is larger than the sum of its proper divisors (2146991).

6440961 is a wasteful number, since it uses less digits than its factorization.

6440961 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2146990.

The product of its (nonzero) digits is 5184, while the sum is 30.

The square root of 6440961 is about 2537.9048445519. The cubic root of 6440961 is about 186.0588032367.

The spelling of 6440961 in words is "six million, four hundred forty thousand, nine hundred sixty-one".