1660438138 has 8 divisors (see below), whose sum is σ = 2499848640. Its totient is φ = 827155260.

The previous prime is 1660438099. The next prime is 1660438141. The reversal of 1660438138 is 8318340661.

It is a happy number.

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

It is a self number, because there is not a number n which added to its sum of digits gives 1660438138.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1531228 + ... + 1532311.

It is an arithmetic number, because the mean of its divisors is an integer number (312481080).

Almost surely, 2^1660438138 is an apocalyptic number.

1660438138 is a deficient number, since it is larger than the sum of its proper divisors (839410502).

1660438138 is a wasteful number, since it uses less digits than its factorization.

1660438138 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3063812.

The product of its (nonzero) digits is 82944, while the sum is 40.

The square root of 1660438138 is about 40748.4740573190. The cubic root of 1660438138 is about 1184.1523103646.

Adding to 1660438138 its reverse (8318340661), we get a palindrome (9978778799).

The spelling of 1660438138 in words is "one billion, six hundred sixty million, four hundred thirty-eight thousand, one hundred thirty-eight".