43020661 has 2 divisors, whose sum is σ = 43020662. Its totient is φ = 43020660.

The previous prime is 43020641. The next prime is 43020671. The reversal of 43020661 is 16602034.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 38316100 + 4704561 = 6190^2 + 2169^2 .

It is a cyclic number.

It is not a de Polignac number, because 43020661 - 2⁵ = 43020629 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (43020611) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21510330 + 21510331.

It is an arithmetic number, because the mean of its divisors is an integer number (21510331).

Almost surely, 2^43020661 is an apocalyptic number.

It is an amenable number.

43020661 is a deficient number, since it is larger than the sum of its proper divisors (1).

43020661 is an equidigital number, since it uses as much as digits as its factorization.

43020661 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 864, while the sum is 22.

The square root of 43020661 is about 6559.0137215896. The cubic root of 43020661 is about 350.3959084551.

Adding to 43020661 its reverse (16602034), we get a palindrome (59622695).

It can be divided in two parts, 43020 and 661, that added together give a square (43681 = 209²).

The spelling of 43020661 in words is "forty-three million, twenty thousand, six hundred sixty-one".