991878130 has 32 divisors (see below), whose sum is σ = 1834430976. Its totient is φ = 385953984.

The previous prime is 991878127. The next prime is 991878131. The reversal of 991878130 is 31878199.

It is not an unprimeable number, because it can be changed into a prime (991878131) 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, 72172 + ... + 84808.

It is an arithmetic number, because the mean of its divisors is an integer number (57325968).

Almost surely, 2^991878130 is an apocalyptic number.

991878130 is a deficient number, since it is larger than the sum of its proper divisors (842552846).

991878130 is a wasteful number, since it uses less digits than its factorization.

991878130 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12858.

The product of its (nonzero) digits is 108864, while the sum is 46.

The square root of 991878130 is about 31494.0967484384. The cubic root of 991878130 is about 997.2853473293.

The spelling of 991878130 in words is "nine hundred ninety-one million, eight hundred seventy-eight thousand, one hundred thirty".