191278877640 has 32 divisors (see below), whose sum is σ = 573836633280. Its totient is φ = 51007700672.

The previous prime is 191278877633. The next prime is 191278877651. The reversal of 191278877640 is 46778872191.

It is a Harshad number since it is a multiple of its sum of digits (60).

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, 796995204 + ... + 796995443.

It is an arithmetic number, because the mean of its divisors is an integer number (17932394790).

Almost surely, 2^191278877640 is an apocalyptic number.

191278877640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

191278877640 is an abundant number, since it is smaller than the sum of its proper divisors (382557755640).

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

191278877640 is a wasteful number, since it uses less digits than its factorization.

191278877640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1593990661 (or 1593990657 counting only the distinct ones).

The product of its (nonzero) digits is 9483264, while the sum is 60.

The spelling of 191278877640 in words is "one hundred ninety-one billion, two hundred seventy-eight million, eight hundred seventy-seven thousand, six hundred forty".