6400949 has 4 divisors (see below), whose sum is σ = 6419436. Its totient is φ = 6382464.

The previous prime is 6400939. The next prime is 6400951. The reversal of 6400949 is 9490046.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 2617924 + 3783025 = 1618^2 + 1945^2 .

It is a cyclic number.

It is not a de Polignac number, because 6400949 - 2¹² = 6396853 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6400939) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8714 + ... + 9419.

It is an arithmetic number, because the mean of its divisors is an integer number (1604859).

Almost surely, 2^6400949 is an apocalyptic number.

It is an amenable number.

6400949 is a deficient number, since it is larger than the sum of its proper divisors (18487).

6400949 is a wasteful number, since it uses less digits than its factorization.

6400949 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18486.

The product of its (nonzero) digits is 7776, while the sum is 32.

The square root of 6400949 is about 2530.0096837759. The cubic root of 6400949 is about 185.6727296989.

It can be divided in two parts, 64009 and 49, that multiplied together give a square (3136441 = 1771²).

The spelling of 6400949 in words is "six million, four hundred thousand, nine hundred forty-nine".