40447861 has 2 divisors, whose sum is σ = 40447862. Its totient is φ = 40447860.

The previous prime is 40447859. The next prime is 40447867. The reversal of 40447861 is 16874404.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 39627025 + 820836 = 6295^2 + 906^2 .

It is a cyclic number.

It is not a de Polignac number, because 40447861 - 2¹ = 40447859 is a prime.

Together with 40447859, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (40447867) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20223930 + 20223931.

It is an arithmetic number, because the mean of its divisors is an integer number (20223931).

Almost surely, 2^40447861 is an apocalyptic number.

It is an amenable number.

40447861 is a deficient number, since it is larger than the sum of its proper divisors (1).

40447861 is an equidigital number, since it uses as much as digits as its factorization.

40447861 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 21504, while the sum is 34.

The square root of 40447861 is about 6359.8632846941. The cubic root of 40447861 is about 343.2668409478.

The spelling of 40447861 in words is "forty million, four hundred forty-seven thousand, eight hundred sixty-one".