6442779 has 16 divisors (see below), whose sum is σ = 10395648. Its totient is φ = 3464832.

The previous prime is 6442771. The next prime is 6442801. The reversal of 6442779 is 9772446.

6442779 = 31² + 32² + ... + 268².

6442779 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 6442779 - 2³ = 6442771 is a prime.

It is an Ulam number.

It is a d-powerful number, because it can be written as 6³ + 4⁶ + 4⁷ + 2¹³ + 7⁶ + 7⁸ + 9⁶ .

6442779 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (6442771) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 8667 + ... + 9380.

It is an arithmetic number, because the mean of its divisors is an integer number (649728).

Almost surely, 2^6442779 is an apocalyptic number.

6442779 is a deficient number, since it is larger than the sum of its proper divisors (3952869).

6442779 is a wasteful number, since it uses less digits than its factorization.

6442779 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18074.

The product of its digits is 84672, while the sum is 39.

The square root of 6442779 is about 2538.2629887386. The cubic root of 6442779 is about 186.0763069956.

The spelling of 6442779 in words is "six million, four hundred forty-two thousand, seven hundred seventy-nine".