1638138298 has 16 divisors (see below), whose sum is σ = 2503319616. Its totient is φ = 803829600.

The previous prime is 1638138289. The next prime is 1638138317. The reversal of 1638138298 is 8928318361.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7611 + ... + 57742.

It is an arithmetic number, because the mean of its divisors is an integer number (156457476).

Almost surely, 2^1638138298 is an apocalyptic number.

1638138298 is a deficient number, since it is larger than the sum of its proper divisors (865181318).

1638138298 is a wasteful number, since it uses less digits than its factorization.

1638138298 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 65589.

The product of its digits is 497664, while the sum is 49.

The square root of 1638138298 is about 40473.9212086005. The cubic root of 1638138298 is about 1178.8273080969.

The spelling of 1638138298 in words is "one billion, six hundred thirty-eight million, one hundred thirty-eight thousand, two hundred ninety-eight".