Search a number
-
+
21369 = 317419
BaseRepresentation
bin101001101111001
31002022110
411031321
51140434
6242533
7116205
oct51571
932273
1021369
1115067
1210449
13995a
147b05
1564e9
hex5379

21369 has 8 divisors (see below), whose sum is σ = 30240. Its totient is φ = 13376.

The previous prime is 21347. The next prime is 21377. The reversal of 21369 is 96312.

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 21369 - 29 = 20857 is a prime.

It is a super-2 number, since 2×213692 = 913268322, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21319) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 159 + ... + 260.

It is an arithmetic number, because the mean of its divisors is an integer number (3780).

221369 is an apocalyptic number.

It is an amenable number.

21369 is a deficient number, since it is larger than the sum of its proper divisors (8871).

21369 is a wasteful number, since it uses less digits than its factorization.

21369 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 439.

The product of its digits is 324, while the sum is 21.

The square root of 21369 is about 146.1813941649. The cubic root of 21369 is about 27.7498985468.

It can be divided in two parts, 2136 and 9, that added together give a triangular number (2145 = T65).

The spelling of 21369 in words is "twenty-one thousand, three hundred sixty-nine".

Divisors: 1 3 17 51 419 1257 7123 21369