921000000 has 196 divisors, whose sum is σ = 3055898384. Its totient is φ = 244800000.

The previous prime is 920999999. The next prime is 921000013. The reversal of 921000000 is 129.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a nialpdrome in base 10.

It is a self number, because there is not a number n which added to its sum of digits gives 921000000.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 27 ways as a sum of consecutive naturals, for example, 2999847 + ... + 3000153.

Almost surely, 2^921000000 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 921000000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1527949192).

921000000 is an abundant number, since it is smaller than the sum of its proper divisors (2134898384).

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

921000000 is an frugal number, since it uses more digits than its factorization.

921000000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 352 (or 317 counting only the distinct ones).

The product of its (nonzero) digits is 18, while the sum is 12.

The square root of 921000000 is about 30347.9818109870. The cubic root of 921000000 is about 972.9410858752.

Adding to 921000000 its reverse (129), we get a palindrome (921000129).

The spelling of 921000000 in words is "nine hundred twenty-one million", and thus it is an aban number.