21053837 has 8 divisors (see below), whose sum is σ = 25477056. Its totient is φ = 16984512.

The previous prime is 21053833. The next prime is 21053839. The reversal of 21053837 is 73835012.

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 21053837 - 2² = 21053833 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21053831) 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, 88343 + ... + 88580.

It is an arithmetic number, because the mean of its divisors is an integer number (3184632).

Almost surely, 2^21053837 is an apocalyptic number.

It is an amenable number.

21053837 is a deficient number, since it is larger than the sum of its proper divisors (4423219).

21053837 is a wasteful number, since it uses less digits than its factorization.

21053837 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 176947.

The product of its (nonzero) digits is 5040, while the sum is 29.

The square root of 21053837 is about 4588.4460332448. The cubic root of 21053837 is about 276.1279818482.

Adding to 21053837 its reverse (73835012), we get a palindrome (94888849).

The spelling of 21053837 in words is "twenty-one million, fifty-three thousand, eight hundred thirty-seven".