1991070 has 24 divisors (see below), whose sum is σ = 5177016. Its totient is φ = 530928.

The previous prime is 1991063. The next prime is 1991071. The reversal of 1991070 is 701991.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1991071) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 10972 + ... + 11151.

It is an arithmetic number, because the mean of its divisors is an integer number (215709).

2^1991070 is an apocalyptic number.

1991070 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1991070 is an abundant number, since it is smaller than the sum of its proper divisors (3185946).

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

1991070 is a wasteful number, since it uses less digits than its factorization.

1991070 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22136 (or 22133 counting only the distinct ones).

The product of its (nonzero) digits is 567, while the sum is 27.

The square root of 1991070 is about 1411.0527984452. The cubic root of 1991070 is about 125.8043069559.

The spelling of 1991070 in words is "one million, nine hundred ninety-one thousand, seventy".