1638768222 has 96 divisors (see below), whose sum is σ = 4379094720. Its totient is φ = 431308800.

The previous prime is 1638768217. The next prime is 1638768251. The reversal of 1638768222 is 2228678361.

1638768222 is a `hidden beast` number, since 1 + 638 + 7 + 6 + 8 + 2 + 2 + 2 = 666.

It is a super-2 number, since 2×1638768222² = 5371122570874082568, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1258972 + ... + 1260272.

It is an arithmetic number, because the mean of its divisors is an integer number (45615570).

Almost surely, 2^1638768222 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1638768222, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2189547360).

1638768222 is an abundant number, since it is smaller than the sum of its proper divisors (2740326498).

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

1638768222 is a wasteful number, since it uses less digits than its factorization.

1638768222 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2098 (or 2095 counting only the distinct ones).

The product of its digits is 387072, while the sum is 45.

The square root of 1638768222 is about 40481.7023110442. The cubic root of 1638768222 is about 1178.9783894499.

The spelling of 1638768222 in words is "one billion, six hundred thirty-eight million, seven hundred sixty-eight thousand, two hundred twenty-two".