409979640 has 128 divisors (see below), whose sum is σ = 1411614720. Its totient is φ = 93312000.

The previous prime is 409979639. The next prime is 409979653. The reversal of 409979640 is 46979904.

It is a self number, because there is not a number n which added to its sum of digits gives 409979640.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 226740 + ... + 228540.

It is an arithmetic number, because the mean of its divisors is an integer number (11028240).

Almost surely, 2^409979640 is an apocalyptic number.

409979640 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 409979640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (705807360).

409979640 is an abundant number, since it is smaller than the sum of its proper divisors (1001635080).

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

409979640 is a wasteful number, since it uses less digits than its factorization.

409979640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2093 (or 2089 counting only the distinct ones).

The product of its (nonzero) digits is 489888, while the sum is 48.

The square root of 409979640 is about 20247.9539707102. The cubic root of 409979640 is about 742.8835869003.

The spelling of 409979640 in words is "four hundred nine million, nine hundred seventy-nine thousand, six hundred forty".