405240240 has 80 divisors (see below), whose sum is σ = 1258276608. Its totient is φ = 107889408.

The previous prime is 405240233. The next prime is 405240281. The reversal of 405240240 is 42042504.

It is a tau number, because it is divible by the number of its divisors (80).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 226389 + ... + 228171.

Almost surely, 2^405240240 is an apocalyptic number.

405240240 is a gapful number since it is divisible by the number (40) formed by its first and last digit.

It is an amenable number.

405240240 is an abundant number, since it is smaller than the sum of its proper divisors (853036368).

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

405240240 is a wasteful number, since it uses less digits than its factorization.

405240240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2746 (or 2740 counting only the distinct ones).

The product of its (nonzero) digits is 1280, while the sum is 21.

The square root of 405240240 is about 20130.5797233959. The cubic root of 405240240 is about 740.0098854292.

Adding to 405240240 its reverse (42042504), we get a palindrome (447282744).

The spelling of 405240240 in words is "four hundred five million, two hundred forty thousand, two hundred forty".