21133430 has 8 divisors (see below), whose sum is σ = 38040192. Its totient is φ = 8453368.

The previous prime is 21133429. The next prime is 21133433. The reversal of 21133430 is 3433112.

It is a happy number.

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

It is a junction number, because it is equal to n+sod(n) for n = 21133399 and 21133408.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21133433) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1056662 + ... + 1056681.

It is an arithmetic number, because the mean of its divisors is an integer number (4755024).

Almost surely, 2^21133430 is an apocalyptic number.

21133430 is a deficient number, since it is larger than the sum of its proper divisors (16906762).

21133430 is a wasteful number, since it uses less digits than its factorization.

21133430 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2113350.

The product of its (nonzero) digits is 216, while the sum is 17.

The square root of 21133430 is about 4597.1110493439. Note that the first 3 decimals coincide. The cubic root of 21133430 is about 276.4755070535.

Adding to 21133430 its reverse (3433112), we get a palindrome (24566542).

The spelling of 21133430 in words is "twenty-one million, one hundred thirty-three thousand, four hundred thirty".