40809840 has 80 divisors (see below), whose sum is σ = 127887648. Its totient is φ = 10764288.

The previous prime is 40809829. The next prime is 40809851. The reversal of 40809840 is 4890804.

It is an interprime number because it is at equal distance from previous prime (40809829) and next prime (40809851).

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

It is a congruent number.

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, 22404 + ... + 24156.

Almost surely, 2^40809840 is an apocalyptic number.

40809840 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 40809840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (63943824).

40809840 is an abundant number, since it is smaller than the sum of its proper divisors (87077808).

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

40809840 is a wasteful number, since it uses less digits than its factorization.

40809840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1866 (or 1860 counting only the distinct ones).

The product of its (nonzero) digits is 9216, while the sum is 33.

The square root of 40809840 is about 6388.2579785103. The cubic root of 40809840 is about 344.2877977345.

The spelling of 40809840 in words is "forty million, eight hundred nine thousand, eight hundred forty".