638629311 has 8 divisors (see below), whose sum is σ = 896321920. Its totient is φ = 403344792.

The previous prime is 638629301. The next prime is 638629333. The reversal of 638629311 is 113926836.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 638629311 - 2⁷ = 638629183 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 638629311.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (638629301) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5601955 + ... + 5602068.

It is an arithmetic number, because the mean of its divisors is an integer number (112040240).

Almost surely, 2^638629311 is an apocalyptic number.

638629311 is a deficient number, since it is larger than the sum of its proper divisors (257692609).

638629311 is a wasteful number, since it uses less digits than its factorization.

638629311 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11204045.

The product of its digits is 46656, while the sum is 39.

The square root of 638629311 is about 25271.1161407643. The cubic root of 638629311 is about 861.1582154640.

The spelling of 638629311 in words is "six hundred thirty-eight million, six hundred twenty-nine thousand, three hundred eleven".