43721897 has 2 divisors, whose sum is σ = 43721898. Its totient is φ = 43721896.

The previous prime is 43721893. The next prime is 43721921. The reversal of 43721897 is 79812734.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 38390416 + 5331481 = 6196^2 + 2309^2 .

It is a cyclic number.

It is not a de Polignac number, because 43721897 - 2² = 43721893 is a prime.

It is not a weakly prime, because it can be changed into another prime (43721893) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21860948 + 21860949.

It is an arithmetic number, because the mean of its divisors is an integer number (21860949).

Almost surely, 2^43721897 is an apocalyptic number.

It is an amenable number.

43721897 is a deficient number, since it is larger than the sum of its proper divisors (1).

43721897 is an equidigital number, since it uses as much as digits as its factorization.

43721897 is an evil number, because the sum of its binary digits is even.

The product of its digits is 84672, while the sum is 41.

The square root of 43721897 is about 6612.2535492826. The cubic root of 43721897 is about 352.2894727337.

The spelling of 43721897 in words is "forty-three million, seven hundred twenty-one thousand, eight hundred ninety-seven".