400000251 has 16 divisors (see below), whose sum is σ = 618623744. Its totient is φ = 225159264.

The previous prime is 400000193. The next prime is 400000261. The reversal of 400000251 is 152000004.

It is not a de Polignac number, because 400000251 - 2¹⁰ = 399999227 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (400000261) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 140740 + ... + 143553.

It is an arithmetic number, because the mean of its divisors is an integer number (38663984).

Almost surely, 2^400000251 is an apocalyptic number.

400000251 is a deficient number, since it is larger than the sum of its proper divisors (218623493).

400000251 is a wasteful number, since it uses less digits than its factorization.

400000251 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 284370.

The product of its (nonzero) digits is 40, while the sum is 12.

The square root of 400000251 is about 20000.0062749990. The cubic root of 400000251 is about 736.8064538434.

Adding to 400000251 its reverse (152000004), we get a palindrome (552000255).

The spelling of 400000251 in words is "four hundred million, two hundred fifty-one", and thus it is an aban number.