43718891 has 2 divisors, whose sum is σ = 43718892. Its totient is φ = 43718890.

The previous prime is 43718827. The next prime is 43718903. The reversal of 43718891 is 19881734.

Added to its reverse (19881734) it gives a square (63600625 = 7975²).

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 43718891 - 2⁶ = 43718827 is a prime.

It is a super-2 number, since 2×43718891² = 3822682860539762, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (43718821) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21859445 + 21859446.

It is an arithmetic number, because the mean of its divisors is an integer number (21859446).

Almost surely, 2^43718891 is an apocalyptic number.

43718891 is a deficient number, since it is larger than the sum of its proper divisors (1).

43718891 is an equidigital number, since it uses as much as digits as its factorization.

43718891 is an evil number, because the sum of its binary digits is even.

The product of its digits is 48384, while the sum is 41.

The square root of 43718891 is about 6612.0262401173. The cubic root of 43718891 is about 352.2813989271.

Adding to 43718891 its reverse (19881734), we get a square (63600625 = 7975²).

The spelling of 43718891 in words is "forty-three million, seven hundred eighteen thousand, eight hundred ninety-one".