638822246400 has 2160 divisors, whose sum is σ = 2772788038020. Its totient is φ = 144388915200.

The previous prime is 638822246369. The next prime is 638822246411. The reversal of 638822246400 is 4642228836.

638822246400 is a `hidden beast` number, since 6 + 388 + 2 + 224 + 6 + 40 + 0 = 666.

It can be written as a sum of positive squares in 18 ways, for example, as 64670524416 + 574151721984 = 254304^2 + 757728^2 .

It is a tau number, because it is divible by the number of its divisors (2160).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a polite number, since it can be written in 179 ways as a sum of consecutive naturals, for example, 15581030380 + ... + 15581030420.

Almost surely, 2^638822246400 is an apocalyptic number.

638822246400 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 638822246400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1386394019010).

638822246400 is an abundant number, since it is smaller than the sum of its proper divisors (2133965791620).

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

638822246400 is a wasteful number, since it uses less digits than its factorization.

638822246400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 132 (or 81 counting only the distinct ones).

The product of its (nonzero) digits is 884736, while the sum is 45.

The spelling of 638822246400 in words is "six hundred thirty-eight billion, eight hundred twenty-two million, two hundred forty-six thousand, four hundred".