427639 has 4 divisors (see below), whose sum is σ = 446256. Its totient is φ = 409024.

The previous prime is 427621. The next prime is 427681. The reversal of 427639 is 936724.

427639 = 73² + 74² + ... + 118².

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

It is a cyclic number.

It is not a de Polignac number, because 427639 - 2¹¹ = 425591 is a prime.

It is a super-2 number, since 2×427639² = 365750228642, which contains 22 as substring.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax 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 427639.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (427619) 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 3 ways as a sum of consecutive naturals, for example, 9274 + ... + 9319.

It is an arithmetic number, because the mean of its divisors is an integer number (111564).

2⁴²⁷⁶³⁹ is an apocalyptic number.

427639 is a deficient number, since it is larger than the sum of its proper divisors (18617).

427639 is a wasteful number, since it uses less digits than its factorization.

427639 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18616.

The product of its digits is 9072, while the sum is 31.

The square root of 427639 is about 653.9411288488. The cubic root of 427639 is about 75.3400264674.

The spelling of 427639 in words is "four hundred twenty-seven thousand, six hundred thirty-nine".