43953661 has 2 divisors, whose sum is σ = 43953662. Its totient is φ = 43953660.

The previous prime is 43953617. The next prime is 43953671. The reversal of 43953661 is 16635934.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 42328036 + 1625625 = 6506^2 + 1275^2 .

It is a cyclic number.

It is not a de Polignac number, because 43953661 - 2⁹ = 43953149 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 43953661.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (43953671) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21976830 + 21976831.

It is an arithmetic number, because the mean of its divisors is an integer number (21976831).

Almost surely, 2^43953661 is an apocalyptic number.

It is an amenable number.

43953661 is a deficient number, since it is larger than the sum of its proper divisors (1).

43953661 is an equidigital number, since it uses as much as digits as its factorization.

43953661 is an evil number, because the sum of its binary digits is even.

The product of its digits is 58320, while the sum is 37.

The square root of 43953661 is about 6629.7557270234. The cubic root of 43953661 is about 352.9108560516.

The spelling of 43953661 in words is "forty-three million, nine hundred fifty-three thousand, six hundred sixty-one".