21049039 has 12 divisors (see below), whose sum is σ = 23463328. Its totient is φ = 18865440.

The previous prime is 21049027. The next prime is 21049103. The reversal of 21049039 is 93094012.

It is a happy number.

It is not a de Polignac number, because 21049039 - 2²¹ = 18951887 is a prime.

It is a hoax number, since the sum of its digits (28) coincides with the sum of the digits of its distinct prime factors.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21048998 and 21049016.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21049019) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 7642 + ... + 10024.

Almost surely, 2^21049039 is an apocalyptic number.

21049039 is a deficient number, since it is larger than the sum of its proper divisors (2414289).

21049039 is a wasteful number, since it uses less digits than its factorization.

21049039 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2478 (or 2467 counting only the distinct ones).

The product of its (nonzero) digits is 1944, while the sum is 28.

The square root of 21049039 is about 4587.9231684936. The cubic root of 21049039 is about 276.1070044730.

The spelling of 21049039 in words is "twenty-one million, forty-nine thousand, thirty-nine".