400031311 has 4 divisors (see below), whose sum is σ = 400262824. Its totient is φ = 399799800.

The previous prime is 400031257. The next prime is 400031329. The reversal of 400031311 is 113130004.

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

It is a cyclic number.

It is not a de Polignac number, because 400031311 - 2⁷ = 400031183 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 400031291 and 400031300.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (460031311) 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, 113145 + ... + 116626.

It is an arithmetic number, because the mean of its divisors is an integer number (100065706).

Almost surely, 2^400031311 is an apocalyptic number.

400031311 is a deficient number, since it is larger than the sum of its proper divisors (231513).

400031311 is a wasteful number, since it uses less digits than its factorization.

400031311 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 231512.

The product of its (nonzero) digits is 36, while the sum is 13.

The square root of 400031311 is about 20000.7827596822. The cubic root of 400031311 is about 736.8255243448.

Adding to 400031311 its reverse (113130004), we get a palindrome (513161315).

It can be divided in two parts, 40003 and 1311, that added together give a palindrome (41314).

The spelling of 400031311 in words is "four hundred million, thirty-one thousand, three hundred eleven".