406391040 has 288 divisors, whose sum is σ = 1574697600. Its totient is φ = 98426880.

The previous prime is 406391021. The next prime is 406391077. The reversal of 406391040 is 40193604.

It is a tau number, because it is divible by the number of its divisors (288).

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a junction number, because it is equal to n+sod(n) for n = 406390995 and 406391013.

It is a congruent number.

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, 379626 + ... + 380694.

It is an arithmetic number, because the mean of its divisors is an integer number (5467700).

Almost surely, 2^406391040 is an apocalyptic number.

406391040 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 406391040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (787348800).

406391040 is an abundant number, since it is smaller than the sum of its proper divisors (1168306560).

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

406391040 is a wasteful number, since it uses less digits than its factorization.

406391040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1110 (or 1090 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 27.

The square root of 406391040 is about 20159.1428389205. The cubic root of 406391040 is about 740.7097159944.

The spelling of 406391040 in words is "four hundred six million, three hundred ninety-one thousand, forty".