28778422211 has 18 divisors (see below), whose sum is σ = 36525296988. Its totient is φ = 22421675640.

The previous prime is 28778422201. The next prime is 28778422229. The reversal of 28778422211 is 11222487782.

It is not a de Polignac number, because 28778422211 - 2⁶ = 28778422147 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28778422201) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 3934820 + ... + 3942126.

It is an arithmetic number, because the mean of its divisors is an integer number (2029183166).

Almost surely, 2^28778422211 is an apocalyptic number.

28778422211 is a deficient number, since it is larger than the sum of its proper divisors (7746874777).

28778422211 is an frugal number, since it uses more digits than its factorization.

28778422211 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14639 (or 7325 counting only the distinct ones).

The product of its digits is 200704, while the sum is 44.

Multiplying 28778422211 by its sum of digits (44), we get a square (1266250577284 = 1125278²).

The spelling of 28778422211 in words is "twenty-eight billion, seven hundred seventy-eight million, four hundred twenty-two thousand, two hundred eleven".