405815940 has 96 divisors (see below), whose sum is σ = 1291973760. Its totient is φ = 105694848.

The previous prime is 405815929. The next prime is 405816013. The reversal of 405815940 is 49518504.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 405815895 and 405815904.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 14482 + ... + 31958.

It is an arithmetic number, because the mean of its divisors is an integer number (13458060).

Almost surely, 2^405815940 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 405815940, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (645986880).

405815940 is an abundant number, since it is smaller than the sum of its proper divisors (886157820).

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

405815940 is a wasteful number, since it uses less digits than its factorization.

405815940 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17538 (or 17530 counting only the distinct ones).

The product of its (nonzero) digits is 28800, while the sum is 36.

The square root of 405815940 is about 20144.8737896270. The cubic root of 405815940 is about 740.3601485292.

The spelling of 405815940 in words is "four hundred five million, eight hundred fifteen thousand, nine hundred forty".