21074 has 8 divisors (see below), whose sum is σ = 32508. Its totient is φ = 10240.

The previous prime is 21067. The next prime is 21089. The reversal of 21074 is 47012.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 21025 + 49 = 145^2 + 7^2 .

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

It is a super-2 number, since 2×21074² = 888226952, which contains 22 as substring.

It is an alternating number because its digits alternate between even and odd.

21074 is an undulating number in base 16.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 47 + ... + 210.

2²¹⁰⁷⁴ is an apocalyptic number.

21074 is a deficient number, since it is larger than the sum of its proper divisors (11434).

21074 is a wasteful number, since it uses less digits than its factorization.

21074 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 300.

The product of its (nonzero) digits is 56, while the sum is 14.

The square root of 21074 is about 145.1688671858. The cubic root of 21074 is about 27.6216101844.

Adding to 21074 its reverse (47012), we get a palindrome (68086).

The spelling of 21074 in words is "twenty-one thousand, seventy-four", and thus it is an iban number.