981821508 has 12 divisors (see below), whose sum is σ = 2290916880. Its totient is φ = 327273832.

The previous prime is 981821507. The next prime is 981821527. The reversal of 981821508 is 805128189.

It is a tau number, because it is divible by the number of its divisors (12).

It is a self number, because there is not a number n which added to its sum of digits gives 981821508.

It is not an unprimeable number, because it can be changed into a prime (981821507) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 40909218 + ... + 40909241.

It is an arithmetic number, because the mean of its divisors is an integer number (190909740).

Almost surely, 2^981821508 is an apocalyptic number.

It is an amenable number.

981821508 is an abundant number, since it is smaller than the sum of its proper divisors (1309095372).

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

981821508 is a wasteful number, since it uses less digits than its factorization.

981821508 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 81818466 (or 81818464 counting only the distinct ones).

The product of its (nonzero) digits is 46080, while the sum is 42.

The square root of 981821508 is about 31334.0311482580. The cubic root of 981821508 is about 993.9034097880.

The spelling of 981821508 in words is "nine hundred eighty-one million, eight hundred twenty-one thousand, five hundred eight".