1621224000 has 672 divisors, whose sum is σ = 6675851520. Its totient is φ = 371712000.

The previous prime is 1621223999. The next prime is 1621224061. The reversal of 1621224000 is 4221261.

1621224000 is a `hidden beast` number, since 1 + 621 + 2 + 2 + 40 + 0 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (18).

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 95 ways as a sum of consecutive naturals, for example, 18215956 + ... + 18216044.

Almost surely, 2^1621224000 is an apocalyptic number.

1621224000 is a gapful number since it is divisible by the number (10) 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 1621224000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3337925760).

1621224000 is an abundant number, since it is smaller than the sum of its proper divisors (5054627520).

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

1621224000 is a wasteful number, since it uses less digits than its factorization.

1621224000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 156 (or 133 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 18.

The square root of 1621224000 is about 40264.4259862226. The cubic root of 1621224000 is about 1174.7560078862.

Adding to 1621224000 its reverse (4221261), we get a palindrome (1625445261).

The spelling of 1621224000 in words is "one billion, six hundred twenty-one million, two hundred twenty-four thousand".