1722240 has 192 divisors, whose sum is σ = 6683040. Its totient is φ = 405504.

The previous prime is 1722211. The next prime is 1722241. The reversal of 1722240 is 422271.

It is a tau number, because it is divible by the number of its divisors (192).

It is a super-2 number, since 2×1722240² = 5932221235200, which contains 22 as substring.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1722241) 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, 74869 + ... + 74891.

2^1722240 is an apocalyptic number.

1722240 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 1722240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3341520).

1722240 is an abundant number, since it is smaller than the sum of its proper divisors (4960800).

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

1722240 is a wasteful number, since it uses less digits than its factorization.

1722240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 61 (or 46 counting only the distinct ones).

The product of its (nonzero) digits is 224, while the sum is 18.

The square root of 1722240 is about 1312.3414189913. The cubic root of 1722240 is about 119.8665182436.

The spelling of 1722240 in words is "one million, seven hundred twenty-two thousand, two hundred forty".