21124131 has 8 divisors (see below), whose sum is σ = 32189184. Its totient is φ = 12070920.

The previous prime is 21124123. The next prime is 21124141. The reversal of 21124131 is 13142112.

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

It is not a de Polignac number, because 21124131 - 2³ = 21124123 is a prime.

It is a super-2 number, since 2×21124131² = 892457821010322, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21124131.

It is not an unprimeable number, because it can be changed into a prime (21124141) 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, 502935 + ... + 502976.

It is an arithmetic number, because the mean of its divisors is an integer number (4023648).

Almost surely, 2^21124131 is an apocalyptic number.

21124131 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

21124131 is a deficient number, since it is larger than the sum of its proper divisors (11065053).

21124131 is a wasteful number, since it uses less digits than its factorization.

21124131 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1005921.

The product of its digits is 48, while the sum is 15.

The square root of 21124131 is about 4596.0995420030. The cubic root of 21124131 is about 276.4349500952.

Adding to 21124131 its reverse (13142112), we get a palindrome (34266243).

It can be divided in two parts, 211 and 24131, that added together give a palindrome (24342).

The spelling of 21124131 in words is "twenty-one million, one hundred twenty-four thousand, one hundred thirty-one".