21133470 has 16 divisors (see below), whose sum is σ = 50720400. Its totient is φ = 5635584.

The previous prime is 21133451. The next prime is 21133477. The reversal of 21133470 is 7433112.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21133477) 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, 352195 + ... + 352254.

It is an arithmetic number, because the mean of its divisors is an integer number (3170025).

Almost surely, 2^21133470 is an apocalyptic number.

21133470 is an abundant number, since it is smaller than the sum of its proper divisors (29586930).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21133470 is a wasteful number, since it uses less digits than its factorization.

21133470 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 704459.

The product of its (nonzero) digits is 504, while the sum is 21.

The square root of 21133470 is about 4597.1153999002. The cubic root of 21133470 is about 276.4756814851.

Adding to 21133470 its reverse (7433112), we get a palindrome (28566582).

The spelling of 21133470 in words is "twenty-one million, one hundred thirty-three thousand, four hundred seventy".