402420240 has 120 divisors (see below), whose sum is σ = 1398135960. Its totient is φ = 103606272.

The previous prime is 402420229. The next prime is 402420253. The reversal of 402420240 is 42024204.

402420240 is a `hidden beast` number, since 4 + 0 + 2 + 420 + 240 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 64448784 + 337971456 = 8028^2 + 18384^2 .

It is a tau number, because it is divible by the number of its divisors (120).

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

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 11244 + ... + 30516.

It is an arithmetic number, because the mean of its divisors is an integer number (11651133).

Almost surely, 2^402420240 is an apocalyptic number.

402420240 is a gapful number since it is divisible by the number (40) 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 402420240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (699067980).

402420240 is an abundant number, since it is smaller than the sum of its proper divisors (995715720).

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

402420240 is a wasteful number, since it uses less digits than its factorization.

402420240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19321 (or 19312 counting only the distinct ones).

The product of its (nonzero) digits is 512, while the sum is 18.

The square root of 402420240 is about 20060.4147514452. The cubic root of 402420240 is about 738.2893526834.

Adding to 402420240 its reverse (42024204), we get a palindrome (444444444).

The spelling of 402420240 in words is "four hundred two million, four hundred twenty thousand, two hundred forty".