1991495130 has 16 divisors (see below), whose sum is σ = 4779588384. Its totient is φ = 531065360.

The previous prime is 1991495119. The next prime is 1991495131. The reversal of 1991495130 is 315941991.

It is not an unprimeable number, because it can be changed into a prime (1991495131) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 33191556 + ... + 33191615.

It is an arithmetic number, because the mean of its divisors is an integer number (298724274).

Almost surely, 2^1991495130 is an apocalyptic number.

1991495130 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1991495130 is an abundant number, since it is smaller than the sum of its proper divisors (2788093254).

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

1991495130 is a wasteful number, since it uses less digits than its factorization.

1991495130 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 66383181.

The product of its (nonzero) digits is 43740, while the sum is 42.

The square root of 1991495130 is about 44626.1709090081. The cubic root of 1991495130 is about 1258.1326016175.

The spelling of 1991495130 in words is "one billion, nine hundred ninety-one million, four hundred ninety-five thousand, one hundred thirty".