21396124 has 12 divisors (see below), whose sum is σ = 37502248. Its totient is φ = 10681200.

The previous prime is 21396119. The next prime is 21396161. The reversal of 21396124 is 42169312.

It is a junction number, because it is equal to n+sod(n) for n = 21396092 and 21396101.

It is a congruent number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 1107 + ... + 6634.

Almost surely, 2^21396124 is an apocalyptic number.

It is an amenable number.

21396124 is a deficient number, since it is larger than the sum of its proper divisors (16106124).

21396124 is a wasteful number, since it uses less digits than its factorization.

21396124 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8436 (or 8434 counting only the distinct ones).

The product of its digits is 2592, while the sum is 28.

The square root of 21396124 is about 4625.5944482845. The cubic root of 21396124 is about 277.6163470678.

The spelling of 21396124 in words is "twenty-one million, three hundred ninety-six thousand, one hundred twenty-four".