21534452 has 12 divisors (see below), whose sum is σ = 38162880. Its totient is φ = 10630776.

The previous prime is 21534451. The next prime is 21534479. The reversal of 21534452 is 25443512.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21534451) 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, 33758 + ... + 34389.

It is an arithmetic number, because the mean of its divisors is an integer number (3180240).

Almost surely, 2^21534452 is an apocalyptic number.

It is an amenable number.

21534452 is a deficient number, since it is larger than the sum of its proper divisors (16628428).

21534452 is a wasteful number, since it uses less digits than its factorization.

21534452 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 68230 (or 68228 counting only the distinct ones).

The product of its digits is 4800, while the sum is 26.

The square root of 21534452 is about 4640.5228153733. The cubic root of 21534452 is about 278.2133345134.

Adding to 21534452 its reverse (25443512), we get a palindrome (46977964).

The spelling of 21534452 in words is "twenty-one million, five hundred thirty-four thousand, four hundred fifty-two".