6447961 has 8 divisors (see below), whose sum is σ = 7023240. Its totient is φ = 5884032.

The previous prime is 6447943. The next prime is 6447967. The reversal of 6447961 is 1697446.

It can be written as a sum of positive squares in 4 ways, for example, as 416025 + 6031936 = 645^2 + 2456^2 .

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 6447961 - 2⁵ = 6447929 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 6447961.

It is not an unprimeable number, because it can be changed into a prime (6447967) 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 7 ways as a sum of consecutive naturals, for example, 1630 + ... + 3943.

It is an arithmetic number, because the mean of its divisors is an integer number (877905).

Almost surely, 2^6447961 is an apocalyptic number.

It is an amenable number.

6447961 is a deficient number, since it is larger than the sum of its proper divisors (575279).

6447961 is a wasteful number, since it uses less digits than its factorization.

6447961 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5675.

The product of its digits is 36288, while the sum is 37.

The square root of 6447961 is about 2539.2835603768. The cubic root of 6447961 is about 186.1261813857.

It can be divided in two parts, 64 and 47961, that multiplied together give a square (3069504 = 1752²).

The spelling of 6447961 in words is "six million, four hundred forty-seven thousand, nine hundred sixty-one".