21454005 has 16 divisors (see below), whose sum is σ = 34890624. Its totient is φ = 11254080.

The previous prime is 21453979. The next prime is 21454007. The reversal of 21454005 is 50045412.

It is not a de Polignac number, because 21454005 - 2⁷ = 21453877 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21454007) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10809 + ... + 12638.

It is an arithmetic number, because the mean of its divisors is an integer number (2180664).

Almost surely, 2^21454005 is an apocalyptic number.

It is an amenable number.

21454005 is a deficient number, since it is larger than the sum of its proper divisors (13436619).

21454005 is a wasteful number, since it uses less digits than its factorization.

21454005 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23516.

The product of its (nonzero) digits is 800, while the sum is 21.

The square root of 21454005 is about 4631.8468238922. The cubic root of 21454005 is about 277.8664584708.

Adding to 21454005 its reverse (50045412), we get a palindrome (71499417).

The spelling of 21454005 in words is "twenty-one million, four hundred fifty-four thousand, five".