400000791 has 4 divisors (see below), whose sum is σ = 533334392. Its totient is φ = 266667192.

The previous prime is 400000789. The next prime is 400000829. The reversal of 400000791 is 197000004.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 400000791 - 2¹ = 400000789 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (400000091) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 66666796 + ... + 66666801.

It is an arithmetic number, because the mean of its divisors is an integer number (133333598).

Almost surely, 2^400000791 is an apocalyptic number.

400000791 is a deficient number, since it is larger than the sum of its proper divisors (133333601).

400000791 is a wasteful number, since it uses less digits than its factorization.

400000791 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 133333600.

The product of its (nonzero) digits is 252, while the sum is 21.

The square root of 400000791 is about 20000.0197749902. The cubic root of 400000791 is about 736.8067854059.

Adding to 400000791 its reverse (197000004), we get a palindrome (597000795).

The spelling of 400000791 in words is "four hundred million, seven hundred ninety-one", and thus it is an aban number.