981491780 has 48 divisors (see below), whose sum is σ = 2084473776. Its totient is φ = 388177920.

The previous prime is 981491779. The next prime is 981491783. The reversal of 981491780 is 87194189.

It can be written as a sum of positive squares in 8 ways, for example, as 96786244 + 884705536 = 9838^2 + 29744^2 .

It is a super-2 number, since 2×981491780² = 1926652228415136800, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (981491783) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 756092 + ... + 757388.

It is an arithmetic number, because the mean of its divisors is an integer number (43426537).

Almost surely, 2^981491780 is an apocalyptic number.

It is an amenable number.

981491780 is an abundant number, since it is smaller than the sum of its proper divisors (1102981996).

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

981491780 is a wasteful number, since it uses less digits than its factorization.

981491780 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1704 (or 1702 counting only the distinct ones).

The product of its (nonzero) digits is 145152, while the sum is 47.

The square root of 981491780 is about 31328.7692065935. The cubic root of 981491780 is about 993.7921354970.

The spelling of 981491780 in words is "nine hundred eighty-one million, four hundred ninety-one thousand, seven hundred eighty".