638073436 has 192 divisors, whose sum is σ = 1587317760. Its totient is φ = 216483840.

The previous prime is 638073419. The next prime is 638073437. The reversal of 638073436 is 634370836.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (638073437) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 8740696 + ... + 8740768.

It is an arithmetic number, because the mean of its divisors is an integer number (8267280).

Almost surely, 2^638073436 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 638073436, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (793658880).

638073436 is an abundant number, since it is smaller than the sum of its proper divisors (949244324).

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

638073436 is a wasteful number, since it uses less digits than its factorization.

638073436 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 204 (or 202 counting only the distinct ones).

The product of its (nonzero) digits is 217728, while the sum is 40.

The square root of 638073436 is about 25260.1155183423. The cubic root of 638073436 is about 860.9082868170.

The spelling of 638073436 in words is "six hundred thirty-eight million, seventy-three thousand, four hundred thirty-six".