400020003 has 12 divisors (see below), whose sum is σ = 578040528. Its totient is φ = 266572080.

The previous prime is 400019999. The next prime is 400020007. The reversal of 400020003 is 300020004.

It is an interprime number because it is at equal distance from previous prime (400019999) and next prime (400020007).

It is not a de Polignac number, because 400020003 - 2² = 400019999 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is not an unprimeable number, because it can be changed into a prime (400020007) by changing a digit.

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 11 ways as a sum of consecutive naturals, for example, 19098 + ... + 34128.

It is an arithmetic number, because the mean of its divisors is an integer number (48170044).

Almost surely, 2^400020003 is an apocalyptic number.

400020003 is a deficient number, since it is larger than the sum of its proper divisors (178020525).

400020003 is a wasteful number, since it uses less digits than its factorization.

400020003 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17994 (or 17991 counting only the distinct ones).

The product of its (nonzero) digits is 24, while the sum is 9.

The square root of 400020003 is about 20000.5000687483. The cubic root of 400020003 is about 736.8185814704.

Adding to 400020003 its reverse (300020004), we get a palindrome (700040007).

Subtracting from 400020003 its reverse (300020004), we obtain a palindrome (99999999).

The spelling of 400020003 in words is "four hundred million, twenty thousand, three".