400229891 has 2 divisors, whose sum is σ = 400229892. Its totient is φ = 400229890.

The previous prime is 400229849. The next prime is 400229897. The reversal of 400229891 is 198922004.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 400229891 - 2¹⁰ = 400228867 is a prime.

It is a super-3 number, since 3×400229891³ (a number of 27 digits) contains 333 as substring.

It is a Sophie Germain prime.

It is equal to p_21347882 and since 400229891 and 21347882 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (400229897) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 200114945 + 200114946.

It is an arithmetic number, because the mean of its divisors is an integer number (200114946).

Almost surely, 2^400229891 is an apocalyptic number.

400229891 is a deficient number, since it is larger than the sum of its proper divisors (1).

400229891 is an equidigital number, since it uses as much as digits as its factorization.

400229891 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 10368, while the sum is 35.

The square root of 400229891 is about 20005.7464494580. The cubic root of 400229891 is about 736.9474269758.

The spelling of 400229891 in words is "four hundred million, two hundred twenty-nine thousand, eight hundred ninety-one".