1640194818 has 32 divisors (see below), whose sum is σ = 3395770560. Its totient is φ = 527526720.

The previous prime is 1640194811. The next prime is 1640194823. The reversal of 1640194818 is 8184910461.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 1640194818.

It is not an unprimeable number, because it can be changed into a prime (1640194811) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 427348 + ... + 431168.

It is an arithmetic number, because the mean of its divisors is an integer number (106117830).

Almost surely, 2^1640194818 is an apocalyptic number.

1640194818 is an abundant number, since it is smaller than the sum of its proper divisors (1755575742).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1640194818 is a wasteful number, since it uses less digits than its factorization.

1640194818 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6322.

The product of its (nonzero) digits is 55296, while the sum is 42.

The square root of 1640194818 is about 40499.3187350108. The cubic root of 1640194818 is about 1179.3204020284.

The spelling of 1640194818 in words is "one billion, six hundred forty million, one hundred ninety-four thousand, eight hundred eighteen".