1980000891 has 24 divisors (see below), whose sum is σ = 3171158640. Its totient is φ = 1180324800.

The previous prime is 1980000881. The next prime is 1980000923.

1980000891 is nontrivially palindromic in base 10.

It is not a de Polignac number, because 1980000891 - 2⁵ = 1980000859 is a prime.

1980000891 is a modest number, since divided by 891 gives 198 as remainder.

It is not an unprimeable number, because it can be changed into a prime (1980000821) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 157896 + ... + 169973.

It is an arithmetic number, because the mean of its divisors is an integer number (132131610).

Almost surely, 2^1980000891 is an apocalyptic number.

1980000891 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

1980000891 is a deficient number, since it is larger than the sum of its proper divisors (1191157749).

1980000891 is a wasteful number, since it uses less digits than its factorization.

1980000891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 327947 (or 327944 counting only the distinct ones).

The product of its (nonzero) digits is 5184, while the sum is 36.

The square root of 1980000891 is about 44497.2009344408. The cubic root of 1980000891 is about 1255.7074239999.

It can be divided in two parts, 1980000 and 891, that added together give a palindrome (1980891).

The spelling of 1980000891 in words is "one billion, nine hundred eighty million, eight hundred ninety-one", and thus it is an aban number.