2421720 has 144 divisors (see below), whose sum is σ = 9294480. Its totient is φ = 535680.

The previous prime is 2421707. The next prime is 2421733. The reversal of 2421720 is 271242.

2421720 = T₅₆ + T₅₇ + ... + T₂₄₄.

It is an interprime number because it is at equal distance from previous prime (2421707) and next prime (2421733).

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

It is a junction number, because it is equal to n+sod(n) for n = 2421693 and 2421702.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 78105 + ... + 78135.

It is an arithmetic number, because the mean of its divisors is an integer number (64545).

2^2421720 is an apocalyptic number.

2421720 is a gapful number since it is divisible by the number (20) 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 2421720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4647240).

2421720 is an abundant number, since it is smaller than the sum of its proper divisors (6872760).

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

2421720 is a wasteful number, since it uses less digits than its factorization.

2421720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 86 (or 48 counting only the distinct ones).

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

The square root of 2421720 is about 1556.1876493534. The cubic root of 2421720 is about 134.2892689136.

Adding to 2421720 its reverse (271242), we get a palindrome (2692962).

The spelling of 2421720 in words is "two million, four hundred twenty-one thousand, seven hundred twenty".