21299528 has 16 divisors (see below), whose sum is σ = 39988080. Its totient is φ = 10636048.

The previous prime is 21299489. The next prime is 21299533. The reversal of 21299528 is 82599212.

It is a junction number, because it is equal to n+sod(n) for n = 21299491 and 21299500.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8375 + ... + 10617.

It is an arithmetic number, because the mean of its divisors is an integer number (2499255).

Almost surely, 2^21299528 is an apocalyptic number.

It is an amenable number.

21299528 is a deficient number, since it is larger than the sum of its proper divisors (18688552).

21299528 is a wasteful number, since it uses less digits than its factorization.

21299528 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3436 (or 3432 counting only the distinct ones).

The product of its digits is 25920, while the sum is 38.

The square root of 21299528 is about 4615.1411679384. The cubic root of 21299528 is about 277.1979366106.

The spelling of 21299528 in words is "twenty-one million, two hundred ninety-nine thousand, five hundred twenty-eight".