28778011 has 2 divisors, whose sum is σ = 28778012. Its totient is φ = 28778010.

The previous prime is 28778003. The next prime is 28778021. The reversal of 28778011 is 11087782.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 28778011 - 2³ = 28778003 is a prime.

It is a super-2 number, since 2×28778011² = 1656347834232242, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (28778021) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14389005 + 14389006.

It is an arithmetic number, because the mean of its divisors is an integer number (14389006).

Almost surely, 2^28778011 is an apocalyptic number.

28778011 is a deficient number, since it is larger than the sum of its proper divisors (1).

28778011 is an equidigital number, since it uses as much as digits as its factorization.

28778011 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6272, while the sum is 34.

The square root of 28778011 is about 5364.5140506853. The cubic root of 28778011 is about 306.4457420852.

The spelling of 28778011 in words is "twenty-eight million, seven hundred seventy-eight thousand, eleven".