6401739 has 8 divisors (see below), whose sum is σ = 8548560. Its totient is φ = 4261376.

The previous prime is 6401723. The next prime is 6401749. The reversal of 6401739 is 9371046.

It is a happy number.

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 6401739 - 2⁴ = 6401723 is a prime.

It is not an unprimeable number, because it can be changed into a prime (6401719) 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 7 ways as a sum of consecutive naturals, for example, 1639 + ... + 3935.

It is an arithmetic number, because the mean of its divisors is an integer number (1068570).

Almost surely, 2^6401739 is an apocalyptic number.

6401739 is a deficient number, since it is larger than the sum of its proper divisors (2146821).

6401739 is a wasteful number, since it uses less digits than its factorization.

6401739 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3229.

The product of its (nonzero) digits is 4536, while the sum is 30.

The square root of 6401739 is about 2530.1658048436. The cubic root of 6401739 is about 185.6803679112.

It can be divided in two parts, 6401 and 739, that added together give a triangular number (7140 = T₁₁₉).

The spelling of 6401739 in words is "six million, four hundred one thousand, seven hundred thirty-nine".