21344777 has 2 divisors, whose sum is σ = 21344778. Its totient is φ = 21344776.

The previous prime is 21344767. The next prime is 21344803. The reversal of 21344777 is 77744312.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19678096 + 1666681 = 4436^2 + 1291^2 .

It is a cyclic number.

It is not a de Polignac number, because 21344777 - 2¹⁰ = 21343753 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (21344717) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10672388 + 10672389.

It is an arithmetic number, because the mean of its divisors is an integer number (10672389).

Almost surely, 2^21344777 is an apocalyptic number.

It is an amenable number.

21344777 is a deficient number, since it is larger than the sum of its proper divisors (1).

21344777 is an equidigital number, since it uses as much as digits as its factorization.

21344777 is an evil number, because the sum of its binary digits is even.

The product of its digits is 32928, while the sum is 35.

The square root of 21344777 is about 4620.0408006856. The cubic root of 21344777 is about 277.3940920963.

The spelling of 21344777 in words is "twenty-one million, three hundred forty-four thousand, seven hundred seventy-seven".