43170421 has 6 divisors (see below), whose sum is σ = 50218710. Its totient is φ = 37003176.

The previous prime is 43170403. The next prime is 43170437. The reversal of 43170421 is 12407134.

It can be written as a sum of positive squares in only one way, i.e., 42380100 + 790321 = 6510^2 + 889^2 .

It is not a de Polignac number, because 43170421 - 2²⁵ = 9615989 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 43170392 and 43170401.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (43170121) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 440466 + ... + 440563.

It is an arithmetic number, because the mean of its divisors is an integer number (8369785).

Almost surely, 2^43170421 is an apocalyptic number.

It is an amenable number.

43170421 is a deficient number, since it is larger than the sum of its proper divisors (7048289).

43170421 is an equidigital number, since it uses as much as digits as its factorization.

43170421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 881043 (or 881036 counting only the distinct ones).

The product of its (nonzero) digits is 672, while the sum is 22.

The square root of 43170421 is about 6570.4201539932. The cubic root of 43170421 is about 350.8020274115.

Adding to 43170421 its reverse (12407134), we get a palindrome (55577555).

The spelling of 43170421 in words is "forty-three million, one hundred seventy thousand, four hundred twenty-one".