981355668 has 48 divisors (see below), whose sum is σ = 2429953344. Its totient is φ = 307187200.

The previous prime is 981355663. The next prime is 981355709. The reversal of 981355668 is 866553189.

It is a Harshad number since it is a multiple of its sum of digits (51).

It is a self number, because there is not a number n which added to its sum of digits gives 981355668.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (981355663) 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, 90118 + ... + 100418.

It is an arithmetic number, because the mean of its divisors is an integer number (50624028).

Almost surely, 2^981355668 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 981355668, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1214976672).

981355668 is an abundant number, since it is smaller than the sum of its proper divisors (1448597676).

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

981355668 is a wasteful number, since it uses less digits than its factorization.

981355668 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10792 (or 10790 counting only the distinct ones).

The product of its digits is 1555200, while the sum is 51.

The square root of 981355668 is about 31326.5968148473. The cubic root of 981355668 is about 993.7461941075.

The spelling of 981355668 in words is "nine hundred eighty-one million, three hundred fifty-five thousand, six hundred sixty-eight".