21425433 has 16 divisors (see below), whose sum is σ = 29793792. Its totient is φ = 13680000.

The previous prime is 21425431. The next prime is 21425471. The reversal of 21425433 is 33452412.

It is not a de Polignac number, because 21425433 - 2¹ = 21425431 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21425431) 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 15 ways as a sum of consecutive naturals, for example, 8253 + ... + 10533.

It is an arithmetic number, because the mean of its divisors is an integer number (1862112).

Almost surely, 2^21425433 is an apocalyptic number.

It is an amenable number.

21425433 is a deficient number, since it is larger than the sum of its proper divisors (8368359).

21425433 is a wasteful number, since it uses less digits than its factorization.

21425433 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2416.

The product of its digits is 2880, while the sum is 24.

The square root of 21425433 is about 4628.7614974202. The cubic root of 21425433 is about 277.7430514041.

Adding to 21425433 its reverse (33452412), we get a palindrome (54877845).

The spelling of 21425433 in words is "twenty-one million, four hundred twenty-five thousand, four hundred thirty-three".