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BaseRepresentation
bin111011011010101
31112201201
413123111
51433141
6352501
7154456
oct73325
945651
1030421
1120946
1215731
1310b01
14b12d
159031
hex76d5

30421 has 4 divisors (see below), whose sum is σ = 31500. Its totient is φ = 29344.

The previous prime is 30403. The next prime is 30427. The reversal of 30421 is 12403.

Adding to 30421 its reverse (12403), we get a palindrome (42824).

It can be divided in two parts, 304 and 21, that added together give a triangular number (325 = T25).

30421 is nontrivially palindromic in base 13.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 12403 = 79157.

It can be written as a sum of positive squares in 2 ways, for example, as 22500 + 7921 = 150^2 + 89^2 .

It is a cyclic number.

It is not a de Polignac number, because 30421 - 25 = 30389 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 30398 and 30407.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (30427) 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, 496 + ... + 553.

It is an arithmetic number, because the mean of its divisors is an integer number (7875).

230421 is an apocalyptic number.

It is an amenable number.

30421 is a deficient number, since it is larger than the sum of its proper divisors (1079).

30421 is a wasteful number, since it uses less digits than its factorization.

30421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1078.

The product of its (nonzero) digits is 24, while the sum is 10.

The square root of 30421 is about 174.4161689752. The cubic root of 30421 is about 31.2169998306.

The spelling of 30421 in words is "thirty thousand, four hundred twenty-one".

Divisors: 1 29 1049 30421