638253400 has 48 divisors (see below), whose sum is σ = 1501857000. Its totient is φ = 252218880.

The previous prime is 638253391. The next prime is 638253419. The reversal of 638253400 is 4352836.

It is a super-2 number, since 2×638253400² = 814734805223120000, 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 11 ways as a sum of consecutive naturals, for example, 2625 + ... + 35824.

Almost surely, 2^638253400 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 638253400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (750928500).

638253400 is an abundant number, since it is smaller than the sum of its proper divisors (863603600).

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

638253400 is a wasteful number, since it uses less digits than its factorization.

638253400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38548 (or 38539 counting only the distinct ones).

The product of its (nonzero) digits is 17280, while the sum is 31.

The square root of 638253400 is about 25263.6774836919. The cubic root of 638253400 is about 860.9892168618.

The spelling of 638253400 in words is "six hundred thirty-eight million, two hundred fifty-three thousand, four hundred".