• 442 can be written using four 4's:

See also 113.

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442 has 8 divisors (see below), whose sum is σ = 756. Its totient is φ = 192.

The previous prime is 439. The next prime is 443. The reversal of 442 is 244.

It is a Cunningham number, because it is equal to 21²+1.

442 is an esthetic number in base 5, because in such base its adjacent digits differ by 1.

It can be written as a sum of positive squares in 2 ways, for example, as 441 + 1 = 21^2 + 1^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

442 is an undulating number in base 5.

Its product of digits (32) is a multiple of the sum of its prime divisors (32).

It is a plaindrome in base 14.

It is a nialpdrome in base 9 and base 10.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (443) 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, 18 + ... + 34.

442 is a deficient number, since it is larger than the sum of its proper divisors (314).

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

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

The sum of its prime factors is 32.

The product of its digits is 32, while the sum is 10.

The square root of 442 is about 21.0237960416. The cubic root of 442 is about 7.6174116031.

Adding to 442 its product of digits (32), we get a palindrome (474).

Adding to 442 its reverse (244), we get a palindrome (686).

It can be divided in two parts, 44 and 2, that multiplied together give a palindrome (88).

The spelling of 442 in words is "four hundred forty-two", and thus it is an aban number and an iban number.