28780011 has 12 divisors (see below), whose sum is σ = 44769088. Its totient is φ = 17710704.

The previous prime is 28780009. The next prime is 28780021. The reversal of 28780011 is 11008782.

It is not a de Polignac number, because 28780011 - 2¹ = 28780009 is a prime.

It is not an unprimeable number, because it can be changed into a prime (28780021) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 122875 + ... + 123108.

Almost surely, 2^28780011 is an apocalyptic number.

28780011 is a deficient number, since it is larger than the sum of its proper divisors (15989077).

28780011 is a wasteful number, since it uses less digits than its factorization.

28780011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 246002 (or 245999 counting only the distinct ones).

The product of its (nonzero) digits is 896, while the sum is 27.

The square root of 28780011 is about 5364.7004576211. The cubic root of 28780011 is about 306.4528409924.

Adding to 28780011 its reverse (11008782), we get a palindrome (39788793).

The spelling of 28780011 in words is "twenty-eight million, seven hundred eighty thousand, eleven".