338721 has 8 divisors (see below), whose sum is σ = 471360. Its totient is φ = 215952.

The previous prime is 338717. The next prime is 338731. The reversal of 338721 is 127833.

338721 is digitally balanced in base 7, because in such base it contains all the possibile digits an equal number of times.

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

It is not a de Polignac number, because 338721 - 2² = 338717 is a prime.

It is a super-2 number, since 2×338721² = 229463831682, which contains 22 as substring.

338721 is strictly pandigital in base 7.

It is a junction number, because it is equal to n+sod(n) for n = 338691 and 338700.

It is not an unprimeable number, because it can be changed into a prime (338731) 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, 2386 + ... + 2523.

It is an arithmetic number, because the mean of its divisors is an integer number (58920).

338721 is a Friedman number, since it can be written as (83*7+1)^2-3, using all its digits and the basic arithmetic operations.

2³³⁸⁷²¹ is an apocalyptic number.

It is an amenable number.

338721 is a deficient number, since it is larger than the sum of its proper divisors (132639).

338721 is a wasteful number, since it uses less digits than its factorization.

338721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4935.

The product of its digits is 1008, while the sum is 24.

The square root of 338721 is about 581.9974226747. The cubic root of 338721 is about 69.7076926409.

The spelling of 338721 in words is "three hundred thirty-eight thousand, seven hundred twenty-one".