28742213 has 2 divisors, whose sum is σ = 28742214. Its totient is φ = 28742212.

The previous prime is 28742201. The next prime is 28742221. The reversal of 28742213 is 31224782.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17032129 + 11710084 = 4127^2 + 3422^2 .

It is a cyclic number.

It is not a de Polignac number, because 28742213 - 2¹² = 28738117 is a prime.

It is a super-3 number, since 3×28742213³ (a number of 23 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28742243) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14371106 + 14371107.

It is an arithmetic number, because the mean of its divisors is an integer number (14371107).

Almost surely, 2^28742213 is an apocalyptic number.

It is an amenable number.

28742213 is a deficient number, since it is larger than the sum of its proper divisors (1).

28742213 is an equidigital number, since it uses as much as digits as its factorization.

28742213 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5376, while the sum is 29.

The square root of 28742213 is about 5361.1764567117. The cubic root of 28742213 is about 306.3186230783.

Adding to 28742213 its reverse (31224782), we get a palindrome (59966995).

The spelling of 28742213 in words is "twenty-eight million, seven hundred forty-two thousand, two hundred thirteen".