21460451 has 4 divisors (see below), whose sum is σ = 21500232. Its totient is φ = 21420672.

The previous prime is 21460447. The next prime is 21460459. The reversal of 21460451 is 15406412.

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

It is a cyclic number.

It is not a de Polignac number, because 21460451 - 2² = 21460447 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21460459) 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, 19070 + ... + 20163.

It is an arithmetic number, because the mean of its divisors is an integer number (5375058).

Almost surely, 2^21460451 is an apocalyptic number.

21460451 is a deficient number, since it is larger than the sum of its proper divisors (39781).

21460451 is an equidigital number, since it uses as much as digits as its factorization.

21460451 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39780.

The product of its (nonzero) digits is 960, while the sum is 23.

The square root of 21460451 is about 4632.5426063880. The cubic root of 21460451 is about 277.8942846325.

Adding to 21460451 its reverse (15406412), we get a palindrome (36866863).

The spelling of 21460451 in words is "twenty-one million, four hundred sixty thousand, four hundred fifty-one".