21142733 has 2 divisors, whose sum is σ = 21142734. Its totient is φ = 21142732.

The previous prime is 21142729. The next prime is 21142741. The reversal of 21142733 is 33724112.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 12369289 + 8773444 = 3517^2 + 2962^2 .

It is a cyclic number.

It is not a de Polignac number, because 21142733 - 2² = 21142729 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21142699 and 21142708.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21142753) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10571366 + 10571367.

It is an arithmetic number, because the mean of its divisors is an integer number (10571367).

Almost surely, 2^21142733 is an apocalyptic number.

It is an amenable number.

21142733 is a deficient number, since it is larger than the sum of its proper divisors (1).

21142733 is an equidigital number, since it uses as much as digits as its factorization.

21142733 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1008, while the sum is 23.

The square root of 21142733 is about 4598.1227691309. The cubic root of 21142733 is about 276.5160695545.

Adding to 21142733 its reverse (33724112), we get a palindrome (54866845).

The spelling of 21142733 in words is "twenty-one million, one hundred forty-two thousand, seven hundred thirty-three".