40221405 has 144 divisors (see below), whose sum is σ = 91231920. Its totient is φ = 16257024.

The previous prime is 40221403. The next prime is 40221409. The reversal of 40221405 is 50412204.

40221405 is a `hidden beast` number, since 40 + 221 + 405 = 666.

It can be written as a sum of positive squares in 8 ways, for example, as 3896676 + 36324729 = 1974^2 + 6027^2 .

It is not a de Polignac number, because 40221405 - 2¹ = 40221403 is a prime.

It is a super-2 number, since 2×40221405² = 3235522840348050, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (40221403) by changing a digit.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 1087047 + ... + 1087083.

It is an arithmetic number, because the mean of its divisors is an integer number (633555).

Almost surely, 2^40221405 is an apocalyptic number.

40221405 is a gapful number since it is divisible by the number (45) formed by its first and last digit.

It is an amenable number.

40221405 is an abundant number, since it is smaller than the sum of its proper divisors (51010515).

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

40221405 is a wasteful number, since it uses less digits than its factorization.

40221405 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 108 (or 98 counting only the distinct ones).

The product of its (nonzero) digits is 320, while the sum is 18.

The square root of 40221405 is about 6342.0347681166. The cubic root of 40221405 is about 342.6250240636.

Adding to 40221405 its reverse (50412204), we get a palindrome (90633609).

It can be divided in two parts, 40 and 221405, that added together give a triangular number (221445 = T₆₆₅).

The spelling of 40221405 in words is "forty million, two hundred twenty-one thousand, four hundred five".