1921842720 has 384 divisors, whose sum is σ = 7850304000. Its totient is φ = 438939648.

The previous prime is 1921842709. The next prime is 1921842721. The reversal of 1921842720 is 272481291.

1921842720 is a `hidden beast` number, since 19 + 218 + 427 + 2 + 0 = 666.

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1921842721) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1481112 + ... + 1482408.

It is an arithmetic number, because the mean of its divisors is an integer number (20443500).

Almost surely, 2^1921842720 is an apocalyptic number.

1921842720 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 1921842720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3925152000).

1921842720 is an abundant number, since it is smaller than the sum of its proper divisors (5928461280).

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

1921842720 is a wasteful number, since it uses less digits than its factorization.

1921842720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1342 (or 1314 counting only the distinct ones).

The product of its (nonzero) digits is 16128, while the sum is 36.

The square root of 1921842720 is about 43838.8266266332. The cubic root of 1921842720 is about 1243.2904974297.

The spelling of 1921842720 in words is "one billion, nine hundred twenty-one million, eight hundred forty-two thousand, seven hundred twenty".