28135649 has 2 divisors, whose sum is σ = 28135650. Its totient is φ = 28135648.

The previous prime is 28135643. The next prime is 28135661. The reversal of 28135649 is 94653182.

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., 20611600 + 7524049 = 4540^2 + 2743^2 .

It is a cyclic number.

It is not a de Polignac number, because 28135649 - 2²⁴ = 11358433 is a prime.

It is a super-2 number, since 2×28135649² = 1583229489302402, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (28135643) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14067824 + 14067825.

It is an arithmetic number, because the mean of its divisors is an integer number (14067825).

Almost surely, 2^28135649 is an apocalyptic number.

It is an amenable number.

28135649 is a deficient number, since it is larger than the sum of its proper divisors (1).

28135649 is an equidigital number, since it uses as much as digits as its factorization.

28135649 is an evil number, because the sum of its binary digits is even.

The product of its digits is 51840, while the sum is 38.

The square root of 28135649 is about 5304.3047612293. The cubic root of 28135649 is about 304.1484767838.

The spelling of 28135649 in words is "twenty-eight million, one hundred thirty-five thousand, six hundred forty-nine".