638369883648 has 160 divisors (see below), whose sum is σ = 2159565112320. Its totient is φ = 182391367680.

The previous prime is 638369883643. The next prime is 638369883703. The reversal of 638369883648 is 846388963836.

It is a super-2 number, since 2×638369883648² (a number of 24 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (638369883643) 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, 3201688 + ... + 3395223.

It is an arithmetic number, because the mean of its divisors is an integer number (13497281952).

Almost surely, 2^638369883648 is an apocalyptic number.

It is an amenable number.

638369883648 is an abundant number, since it is smaller than the sum of its proper divisors (1521195228672).

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

638369883648 is an equidigital number, since it uses as much as digits as its factorization.

638369883648 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6596945 (or 6596923 counting only the distinct ones).

The product of its digits is 859963392, while the sum is 72.

The spelling of 638369883648 in words is "six hundred thirty-eight billion, three hundred sixty-nine million, eight hundred eighty-three thousand, six hundred forty-eight".