40289920 has 128 divisors (see below), whose sum is σ = 107956800. Its totient is φ = 14254080.

The previous prime is 40289891. The next prime is 40289923. The reversal of 40289920 is 2998204.

It is a tau number, because it is divible by the number of its divisors (128).

It is not an unprimeable number, because it can be changed into a prime (40289923) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 415312 + ... + 415408.

Almost surely, 2^40289920 is an apocalyptic number.

40289920 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 40289920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (53978400).

40289920 is an abundant number, since it is smaller than the sum of its proper divisors (67666880).

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

40289920 is a wasteful number, since it uses less digits than its factorization.

40289920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 186 (or 174 counting only the distinct ones).

The product of its (nonzero) digits is 10368, while the sum is 34.

The square root of 40289920 is about 6347.4341272675. The cubic root of 40289920 is about 342.8194614673.

It can be divided in two parts, 40289 and 920, that added together give a square (41209 = 203²).

The spelling of 40289920 in words is "forty million, two hundred eighty-nine thousand, nine hundred twenty".