400401321 has 4 divisors (see below), whose sum is σ = 533868432. Its totient is φ = 266934212.

The previous prime is 400401311. The next prime is 400401329. The reversal of 400401321 is 123104004.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 400401321 - 2⁶ = 400401257 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 400401321.

It is not an unprimeable number, because it can be changed into a prime (400401329) 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, 66733551 + ... + 66733556.

It is an arithmetic number, because the mean of its divisors is an integer number (133467108).

Almost surely, 2^400401321 is an apocalyptic number.

It is an amenable number.

400401321 is a deficient number, since it is larger than the sum of its proper divisors (133467111).

400401321 is a wasteful number, since it uses less digits than its factorization.

400401321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 133467110.

The product of its (nonzero) digits is 96, while the sum is 15.

The square root of 400401321 is about 20010.0305097219. The cubic root of 400401321 is about 737.0526305658.

Adding to 400401321 its reverse (123104004), we get a palindrome (523505325).

The spelling of 400401321 in words is "four hundred million, four hundred one thousand, three hundred twenty-one".