405809040 has 320 divisors, whose sum is σ = 1640894976. Its totient is φ = 80510976.

The previous prime is 405809039. The next prime is 405809101. The reversal of 405809040 is 40908504.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 405808989 and 405809007.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 370734 + ... + 371826.

Almost surely, 2^405809040 is an apocalyptic number.

405809040 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 405809040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (820447488).

405809040 is an abundant number, since it is smaller than the sum of its proper divisors (1235085936).

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

405809040 is a wasteful number, since it uses less digits than its factorization.

405809040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1146 (or 1140 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 30.

The square root of 405809040 is about 20144.7025294493. The cubic root of 405809040 is about 740.3559524447.

The spelling of 405809040 in words is "four hundred five million, eight hundred nine thousand, forty".