20894222778 has 32 divisors (see below), whose sum is σ = 49094119872. Its totient is φ = 5844537600.

The previous prime is 20894222747. The next prime is 20894222779. The reversal of 20894222778 is 87722249802.

It is a self number, because there is not a number n which added to its sum of digits gives 20894222778.

It is not an unprimeable number, because it can be changed into a prime (20894222779) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 12175263 + ... + 12176978.

It is an arithmetic number, because the mean of its divisors is an integer number (1534191246).

Almost surely, 2^20894222778 is an apocalyptic number.

20894222778 is an abundant number, since it is smaller than the sum of its proper divisors (28199897094).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20894222778 is a wasteful number, since it uses less digits than its factorization.

20894222778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24352270.

The product of its (nonzero) digits is 1806336, while the sum is 51.

The spelling of 20894222778 in words is "twenty billion, eight hundred ninety-four million, two hundred twenty-two thousand, seven hundred seventy-eight".