6401647 has 4 divisors (see below), whose sum is σ = 7316176. Its totient is φ = 5487120.

The previous prime is 6401621. The next prime is 6401669. The reversal of 6401647 is 7461046.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-6401647 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6401687) 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, 457254 + ... + 457267.

It is an arithmetic number, because the mean of its divisors is an integer number (1829044).

Almost surely, 2^6401647 is an apocalyptic number.

6401647 is a deficient number, since it is larger than the sum of its proper divisors (914529).

6401647 is an equidigital number, since it uses as much as digits as its factorization.

6401647 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 914528.

The product of its (nonzero) digits is 4032, while the sum is 28.

The square root of 6401647 is about 2530.1476241516. The cubic root of 6401647 is about 185.6794784302.

The spelling of 6401647 in words is "six million, four hundred one thousand, six hundred forty-seven".