43609421 has 4 divisors (see below), whose sum is σ = 44788092. Its totient is φ = 42430752.

The previous prime is 43609393. The next prime is 43609441. The reversal of 43609421 is 12490634.

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 33756100 + 9853321 = 5810^2 + 3139^2 .

It is a cyclic number.

It is not a de Polignac number, because 43609421 - 2¹⁸ = 43347277 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (43609441) 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, 589280 + ... + 589353.

It is an arithmetic number, because the mean of its divisors is an integer number (11197023).

Almost surely, 2^43609421 is an apocalyptic number.

It is an amenable number.

43609421 is a deficient number, since it is larger than the sum of its proper divisors (1178671).

43609421 is a wasteful number, since it uses less digits than its factorization.

43609421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1178670.

The product of its (nonzero) digits is 5184, while the sum is 29.

The square root of 43609421 is about 6603.7429538104. The cubic root of 43609421 is about 351.9871212790.

The spelling of 43609421 in words is "forty-three million, six hundred nine thousand, four hundred twenty-one".