1321920 has 168 divisors, whose sum is σ = 4992624. Its totient is φ = 331776.

The previous prime is 1321919. The next prime is 1321927. The reversal of 1321920 is 291231.

It is a happy number.

It is a hoax number, since the sum of its digits (18) 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 (18).

It is a nialpdrome in base 6.

It is a zygodrome in base 4.

It is a junction number, because it is equal to n+sod(n) for n = 1321893 and 1321902.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1321927) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 77752 + ... + 77768.

It is an arithmetic number, because the mean of its divisors is an integer number (29718).

2^1321920 is an apocalyptic number.

1321920 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 1321920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2496312).

1321920 is an abundant number, since it is smaller than the sum of its proper divisors (3670704).

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

1321920 is an equidigital number, since it uses as much as digits as its factorization.

1321920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 49 (or 27 counting only the distinct ones).

The product of its (nonzero) digits is 108, while the sum is 18.

The square root of 1321920 is about 1149.7477984323. The cubic root of 1321920 is about 109.7492912853.

The spelling of 1321920 in words is "one million, three hundred twenty-one thousand, nine hundred twenty".