400405530 has 32 divisors (see below), whose sum is σ = 1098255744. Its totient is φ = 91521216.

The previous prime is 400405519. The next prime is 400405547. The reversal of 400405530 is 35504004.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a junction number, because it is equal to n+sod(n) for n = 400405497 and 400405506.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 953137 + ... + 953556.

It is an arithmetic number, because the mean of its divisors is an integer number (34320492).

Almost surely, 2^400405530 is an apocalyptic number.

400405530 is an abundant number, since it is smaller than the sum of its proper divisors (697850214).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

400405530 is a wasteful number, since it uses less digits than its factorization.

400405530 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1906710.

The product of its (nonzero) digits is 1200, while the sum is 21.

The square root of 400405530 is about 20010.1356816989. The cubic root of 400405530 is about 737.0552131777.

Adding to 400405530 its reverse (35504004), we get a palindrome (435909534).

The spelling of 400405530 in words is "four hundred million, four hundred five thousand, five hundred thirty".