40320421 has 4 divisors (see below), whose sum is σ = 40498272. Its totient is φ = 40142572.

The previous prime is 40320391. The next prime is 40320431. The reversal of 40320421 is 12402304.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-40320421 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 40320395 and 40320404.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (40320431) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 88585 + ... + 89038.

It is an arithmetic number, because the mean of its divisors is an integer number (10124568).

Almost surely, 2^40320421 is an apocalyptic number.

It is an amenable number.

40320421 is a deficient number, since it is larger than the sum of its proper divisors (177851).

40320421 is a wasteful number, since it uses less digits than its factorization.

40320421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 177850.

The product of its (nonzero) digits is 192, while the sum is 16.

The square root of 40320421 is about 6349.8362971025. The cubic root of 40320421 is about 342.9059487648.

Adding to 40320421 its reverse (12402304), we get a palindrome (52722725).

It can be divided in two parts, 403204 and 21, that added together give a square (403225 = 635²).

The spelling of 40320421 in words is "forty million, three hundred twenty thousand, four hundred twenty-one".