43653421 has 4 divisors (see below), whose sum is σ = 49889632. Its totient is φ = 37417212.

The previous prime is 43653413. The next prime is 43653443. The reversal of 43653421 is 12435634.

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, and also an emirpimes, since its reverse is a distinct semiprime: 12435634 = 2 ⋅6217817.

It is not a de Polignac number, because 43653421 - 2³ = 43653413 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 43653421.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (43653461) 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, 3118095 + ... + 3118108.

It is an arithmetic number, because the mean of its divisors is an integer number (12472408).

Almost surely, 2^43653421 is an apocalyptic number.

It is an amenable number.

43653421 is a deficient number, since it is larger than the sum of its proper divisors (6236211).

43653421 is an equidigital number, since it uses as much as digits as its factorization.

43653421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6236210.

The product of its digits is 8640, while the sum is 28.

The square root of 43653421 is about 6607.0735579377. The cubic root of 43653421 is about 352.1054613623.

The spelling of 43653421 in words is "forty-three million, six hundred fifty-three thousand, four hundred twenty-one".