21235454 has 4 divisors (see below), whose sum is σ = 31853184. Its totient is φ = 10617726.

The previous prime is 21235427. The next prime is 21235517. The reversal of 21235454 is 45453212.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a super-2 number, since 2×21235454² = 901889013172232, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5308862 + ... + 5308865.

It is an arithmetic number, because the mean of its divisors is an integer number (7963296).

Almost surely, 2^21235454 is an apocalyptic number.

21235454 is a deficient number, since it is larger than the sum of its proper divisors (10617730).

21235454 is a wasteful number, since it uses less digits than its factorization.

21235454 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10617729.

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

The square root of 21235454 is about 4608.1942233374. The cubic root of 21235454 is about 276.9196985145.

Adding to 21235454 its reverse (45453212), we get a palindrome (66688666).

The spelling of 21235454 in words is "twenty-one million, two hundred thirty-five thousand, four hundred fifty-four".