40345421 has 4 divisors (see below), whose sum is σ = 40898172. Its totient is φ = 39792672.

The previous prime is 40345399. The next prime is 40345423. The reversal of 40345421 is 12454304.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 14478025 + 25867396 = 3805^2 + 5086^2 .

It is a cyclic number.

It is not a de Polignac number, because 40345421 - 2²² = 36151117 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (40345423) 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, 276266 + ... + 276411.

It is an arithmetic number, because the mean of its divisors is an integer number (10224543).

Almost surely, 2^40345421 is an apocalyptic number.

It is an amenable number.

40345421 is a deficient number, since it is larger than the sum of its proper divisors (552751).

40345421 is an equidigital number, since it uses as much as digits as its factorization.

40345421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 552750.

The product of its (nonzero) digits is 1920, while the sum is 23.

The square root of 40345421 is about 6351.8045467410. The cubic root of 40345421 is about 342.9768051475.

Adding to 40345421 its reverse (12454304), we get a palindrome (52799725).

The spelling of 40345421 in words is "forty million, three hundred forty-five thousand, four hundred twenty-one".