21345454 has 16 divisors (see below), whose sum is σ = 34590528. Its totient is φ = 9820512.

The previous prime is 21345451. The next prime is 21345469. The reversal of 21345454 is 45454312.

It is a super-2 number, since 2×21345454² = 911256812932232, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21345451) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8424 + ... + 10660.

It is an arithmetic number, because the mean of its divisors is an integer number (2161908).

Almost surely, 2^21345454 is an apocalyptic number.

21345454 is a deficient number, since it is larger than the sum of its proper divisors (13245074).

21345454 is a wasteful number, since it uses less digits than its factorization.

21345454 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2619.

The product of its digits is 9600, while the sum is 28.

The square root of 21345454 is about 4620.1140678559. The cubic root of 21345454 is about 277.3970248015.

Adding to 21345454 its reverse (45454312), we get a palindrome (66799766).

The spelling of 21345454 in words is "twenty-one million, three hundred forty-five thousand, four hundred fifty-four".