1638254242944 has 672 divisors, whose sum is σ = 5406898196700. Its totient is φ = 493836963840.

The previous prime is 1638254242921. The next prime is 1638254242949. The reversal of 1638254242944 is 4492424528361.

1638254242944 is a `hidden beast` number, since 1 + 6 + 3 + 8 + 2 + 542 + 4 + 2 + 94 + 4 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 1615847745600 + 22406497344 = 1271160^2 + 149688^2 .

It is a Harshad number since it is a multiple of its sum of digits (54).

It is not an unprimeable number, because it can be changed into a prime (1638254242949) by changing a digit.

It is a polite number, since it can be written in 83 ways as a sum of consecutive naturals, for example, 4211450302 + ... + 4211450690.

Almost surely, 2^{1638254242944} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1638254242944, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2703449098350).

1638254242944 is an abundant number, since it is smaller than the sum of its proper divisors (3768643953756).

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

1638254242944 is an equidigital number, since it uses as much as digits as its factorization.

1638254242944 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 816 (or 778 counting only the distinct ones).

The product of its digits is 13271040, while the sum is 54.

The spelling of 1638254242944 in words is "one trillion, six hundred thirty-eight billion, two hundred fifty-four million, two hundred forty-two thousand, nine hundred forty-four".