400021847 has 2 divisors, whose sum is σ = 400021848. Its totient is φ = 400021846.

The previous prime is 400021813. The next prime is 400021859. The reversal of 400021847 is 748120004.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 400021847 - 2¹⁶ = 399956311 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (400021807) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 200010923 + 200010924.

It is an arithmetic number, because the mean of its divisors is an integer number (200010924).

Almost surely, 2^400021847 is an apocalyptic number.

400021847 is a deficient number, since it is larger than the sum of its proper divisors (1).

400021847 is an equidigital number, since it uses as much as digits as its factorization.

400021847 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1792, while the sum is 26.

The square root of 400021847 is about 20000.5461675425. The cubic root of 400021847 is about 736.8197136566.

The spelling of 400021847 in words is "four hundred million, twenty-one thousand, eight hundred forty-seven".