43421881 has 2 divisors, whose sum is σ = 43421882. Its totient is φ = 43421880.

The previous prime is 43421879. The next prime is 43421909. The reversal of 43421881 is 18812434.

43421881 = 4659² + 4660².

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21715600 + 21706281 = 4660^2 + 4659^2 .

It is a cyclic number.

It is not a de Polignac number, because 43421881 - 2¹ = 43421879 is a prime.

It is a super-2 number, since 2×43421881² = 3770919499156322, which contains 22 as substring.

Together with 43421879, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (43422881) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21710940 + 21710941.

It is an arithmetic number, because the mean of its divisors is an integer number (21710941).

Almost surely, 2^43421881 is an apocalyptic number.

43421881 is the 4660-th centered square number.

It is an amenable number.

43421881 is a deficient number, since it is larger than the sum of its proper divisors (1).

43421881 is an equidigital number, since it uses as much as digits as its factorization.

43421881 is an evil number, because the sum of its binary digits is even.

The product of its digits is 6144, while the sum is 31.

The square root of 43421881 is about 6589.5281318164. The cubic root of 43421881 is about 351.4818289477.

The spelling of 43421881 in words is "forty-three million, four hundred twenty-one thousand, eight hundred eighty-one".