43120021 has 4 divisors (see below), whose sum is σ = 49280032. Its totient is φ = 36960012.

The previous prime is 43120019. The next prime is 43120027. The reversal of 43120021 is 12002134.

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 not a de Polignac number, because 43120021 - 2¹ = 43120019 is a prime.

It is a super-2 number, since 2×43120021² = 3718672422080882, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 43119983 and 43120010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (43120027) 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, 3079995 + ... + 3080008.

It is an arithmetic number, because the mean of its divisors is an integer number (12320008).

Almost surely, 2^43120021 is an apocalyptic number.

It is an amenable number.

43120021 is a deficient number, since it is larger than the sum of its proper divisors (6160011).

43120021 is an equidigital number, since it uses as much as digits as its factorization.

43120021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6160010.

The product of its (nonzero) digits is 48, while the sum is 13.

The square root of 43120021 is about 6566.5836627580. The cubic root of 43120021 is about 350.6654577675.

Adding to 43120021 its reverse (12002134), we get a palindrome (55122155).

The spelling of 43120021 in words is "forty-three million, one hundred twenty thousand, twenty-one".