21135452 has 36 divisors (see below), whose sum is σ = 41001240. Its totient is φ = 9473952.

The previous prime is 21135451. The next prime is 21135479. The reversal of 21135452 is 25453112.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21135451) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 254603 + ... + 254685.

Almost surely, 2^21135452 is an apocalyptic number.

It is an amenable number.

21135452 is a deficient number, since it is larger than the sum of its proper divisors (19865788).

21135452 is a wasteful number, since it uses less digits than its factorization.

21135452 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 242 (or 157 counting only the distinct ones).

The product of its digits is 1200, while the sum is 23.

The square root of 21135452 is about 4597.3309648099. The cubic root of 21135452 is about 276.4843242947.

Adding to 21135452 its reverse (25453112), we get a palindrome (46588564).

The spelling of 21135452 in words is "twenty-one million, one hundred thirty-five thousand, four hundred fifty-two".