638619499 has 12 divisors (see below), whose sum is σ = 766849728. Its totient is φ = 529729200.

The previous prime is 638619479. The next prime is 638619521. The reversal of 638619499 is 994916836.

It is not a de Polignac number, because 638619499 - 2⁹ = 638618987 is a prime.

It is a super-2 number, since 2×638619499² = 815669729006022002, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (638619439) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 208692 + ... + 211729.

It is an arithmetic number, because the mean of its divisors is an integer number (63904144).

Almost surely, 2^638619499 is an apocalyptic number.

638619499 is a deficient number, since it is larger than the sum of its proper divisors (128230229).

638619499 is a wasteful number, since it uses less digits than its factorization.

638619499 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 420466 (or 420459 counting only the distinct ones).

The product of its digits is 2519424, while the sum is 55.

The square root of 638619499 is about 25270.9220053404. The cubic root of 638619499 is about 861.1538051186.

The spelling of 638619499 in words is "six hundred thirty-eight million, six hundred nineteen thousand, four hundred ninety-nine".