21154673 has 2 divisors, whose sum is σ = 21154674. Its totient is φ = 21154672.

The previous prime is 21154669. The next prime is 21154709. The reversal of 21154673 is 37645112.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15547249 + 5607424 = 3943^2 + 2368^2 .

It is a cyclic number.

It is not a de Polignac number, because 21154673 - 2² = 21154669 is a prime.

It is not a weakly prime, because it can be changed into another prime (21154603) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10577336 + 10577337.

It is an arithmetic number, because the mean of its divisors is an integer number (10577337).

Almost surely, 2^21154673 is an apocalyptic number.

It is an amenable number.

21154673 is a deficient number, since it is larger than the sum of its proper divisors (1).

21154673 is an equidigital number, since it uses as much as digits as its factorization.

21154673 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5040, while the sum is 29.

The square root of 21154673 is about 4599.4209418143. The cubic root of 21154673 is about 276.5681123463.

Adding to 21154673 its reverse (37645112), we get a palindrome (58799785).

The spelling of 21154673 in words is "twenty-one million, one hundred fifty-four thousand, six hundred seventy-three".