40561920 has 216 divisors, whose sum is σ = 160707456. Its totient is φ = 9252864.

The previous prime is 40561909. The next prime is 40561921. The reversal of 40561920 is 2916504.

40561920 is a `hidden beast` number, since 40 + 5 + 619 + 2 + 0 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (40561921) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 80389 + ... + 80891.

It is an arithmetic number, because the mean of its divisors is an integer number (744016).

Almost surely, 2^40561920 is an apocalyptic number.

40561920 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 40561920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (80353728).

40561920 is an abundant number, since it is smaller than the sum of its proper divisors (120145536).

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

40561920 is a wasteful number, since it uses less digits than its factorization.

40561920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 537 (or 520 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 27.

The square root of 40561920 is about 6368.8240672828. The cubic root of 40561920 is about 343.5891977380.

The spelling of 40561920 in words is "forty million, five hundred sixty-one thousand, nine hundred twenty".