19991080 has 32 divisors (see below), whose sum is σ = 45152640. Its totient is φ = 7965760.

The previous prime is 19991077. The next prime is 19991089. The reversal of 19991080 is 8019991.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19991089) 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, 11637 + ... + 13243.

It is an arithmetic number, because the mean of its divisors is an integer number (1411020).

Almost surely, 2^19991080 is an apocalyptic number.

19991080 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

19991080 is an abundant number, since it is smaller than the sum of its proper divisors (25161560).

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

19991080 is a wasteful number, since it uses less digits than its factorization.

19991080 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1929 (or 1925 counting only the distinct ones).

The product of its (nonzero) digits is 5832, while the sum is 37.

The square root of 19991080 is about 4471.1385574594. The cubic root of 19991080 is about 271.4014013168.

The spelling of 19991080 in words is "nineteen million, nine hundred ninety-one thousand, eighty".