188640749840 has 20 divisors (see below), whose sum is σ = 438589743564. Its totient is φ = 75456299904.

The previous prime is 188640749837. The next prime is 188640749851. The reversal of 188640749840 is 48947046881.

It can be written as a sum of positive squares in 2 ways, for example, as 40597414144 + 148043335696 = 201488^2 + 384764^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is a self number, because there is not a number n which added to its sum of digits gives 188640749840.

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, 1179004607 + ... + 1179004766.

Almost surely, 2^188640749840 is an apocalyptic number.

188640749840 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

188640749840 is an abundant number, since it is smaller than the sum of its proper divisors (249948993724).

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

188640749840 is a wasteful number, since it uses less digits than its factorization.

188640749840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2358009386 (or 2358009380 counting only the distinct ones).

The product of its (nonzero) digits is 12386304, while the sum is 59.

The spelling of 188640749840 in words is "one hundred eighty-eight billion, six hundred forty million, seven hundred forty-nine thousand, eight hundred forty".