400891171 has 2 divisors, whose sum is σ = 400891172. Its totient is φ = 400891170.

The previous prime is 400891133. The next prime is 400891187. The reversal of 400891171 is 171198004.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 400891171 - 2¹¹ = 400889123 is a prime.

It is not a weakly prime, because it can be changed into another prime (400894171) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 200445585 + 200445586.

It is an arithmetic number, because the mean of its divisors is an integer number (200445586).

Almost surely, 2^400891171 is an apocalyptic number.

400891171 is a deficient number, since it is larger than the sum of its proper divisors (1).

400891171 is an equidigital number, since it uses as much as digits as its factorization.

400891171 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2016, while the sum is 31.

The square root of 400891171 is about 20022.2668796518. The cubic root of 400891171 is about 737.3530775409.

The spelling of 400891171 in words is "four hundred million, eight hundred ninety-one thousand, one hundred seventy-one".