638977283 has 32 divisors (see below), whose sum is σ = 812519424. Its totient is φ = 489595392.

The previous prime is 638977253. The next prime is 638977303. The reversal of 638977283 is 382779836.

It is a happy number.

It is a Cunningham number, because it is equal to 25278²-1.

It is a cyclic number.

It is not a de Polignac number, because 638977283 - 2²⁸ = 370541827 is a prime.

It is a Smith number, since the sum of its digits (53) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (638977223) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 428966 + ... + 430452.

It is an arithmetic number, because the mean of its divisors is an integer number (25391232).

Almost surely, 2^638977283 is an apocalyptic number.

638977283 is a deficient number, since it is larger than the sum of its proper divisors (173542141).

638977283 is a wasteful number, since it uses less digits than its factorization.

638977283 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1691.

The product of its digits is 3048192, while the sum is 53.

The square root of 638977283 is about 25277.9999802200. Note that the first 4 decimals coincide. The cubic root of 638977283 is about 861.3145944111.

The spelling of 638977283 in words is "six hundred thirty-eight million, nine hundred seventy-seven thousand, two hundred eighty-three".