1921229568 has 216 divisors, whose sum is σ = 5919391296. Its totient is φ = 597196800.

The previous prime is 1921229543. The next prime is 1921229573. The reversal of 1921229568 is 8659221291.

It is a happy number.

It is a super-2 number, since 2×1921229568² = 7382246105914933248, which contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 7089273 + ... + 7089543.

Almost surely, 2^1921229568 is an apocalyptic number.

1921229568 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1921229568, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2959695648).

1921229568 is an abundant number, since it is smaller than the sum of its proper divisors (3998161728).

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

1921229568 is a wasteful number, since it uses less digits than its factorization.

1921229568 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 491 (or 474 counting only the distinct ones).

The product of its digits is 155520, while the sum is 45.

The square root of 1921229568 is about 43831.8328158885. The cubic root of 1921229568 is about 1243.1582619918.

The spelling of 1921229568 in words is "one billion, nine hundred twenty-one million, two hundred twenty-nine thousand, five hundred sixty-eight".