401520240 has 400 divisors, whose sum is σ = 1568578176. Its totient is φ = 94348800.

The previous prime is 401520233. The next prime is 401520241. The reversal of 401520240 is 42025104.

401520240 is a `hidden beast` number, since 401 + 5 + 20 + 240 = 666.

It is a super-2 number, since 2×401520240² = 322437006259315200, 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 (401520241) by changing a digit.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 3064975 + ... + 3065105.

Almost surely, 2^401520240 is an apocalyptic number.

401520240 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 401520240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (784289088).

401520240 is an abundant number, since it is smaller than the sum of its proper divisors (1167057936).

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

401520240 is a wasteful number, since it uses less digits than its factorization.

401520240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 210 (or 195 counting only the distinct ones).

The product of its (nonzero) digits is 320, while the sum is 18.

The square root of 401520240 is about 20037.9699570590. The cubic root of 401520240 is about 737.7385550214.

Adding to 401520240 its reverse (42025104), we get a palindrome (443545344).

The spelling of 401520240 in words is "four hundred one million, five hundred twenty thousand, two hundred forty".