1980181836 has 144 divisors (see below), whose sum is σ = 5389372800. Its totient is φ = 628554816.

The previous prime is 1980181807. The next prime is 1980181871. The reversal of 1980181836 is 6381810891.

It is a super-2 number, since 2×1980181836² = 7842240207248661792, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1980181791 and 1980181800.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 8723155 + ... + 8723381.

It is an arithmetic number, because the mean of its divisors is an integer number (37426200).

Almost surely, 2^1980181836 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1980181836, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2694686400).

1980181836 is an abundant number, since it is smaller than the sum of its proper divisors (3409190964).

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

1980181836 is a wasteful number, since it uses less digits than its factorization.

1980181836 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 373 (or 328 counting only the distinct ones).

The product of its (nonzero) digits is 82944, while the sum is 45.

The square root of 1980181836 is about 44499.2341057686. The cubic root of 1980181836 is about 1255.7456743293.

The spelling of 1980181836 in words is "one billion, nine hundred eighty million, one hundred eighty-one thousand, eight hundred thirty-six".