400021013 has 8 divisors (see below), whose sum is σ = 458231040. Its totient is φ = 342077040.

The previous prime is 400021007. The next prime is 400021019. The reversal of 400021013 is 310120004.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (400021007) and next prime (400021019).

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 400021013 - 2²⁰ = 398972437 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 400020985 and 400021003.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (400021019) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 63278 + ... + 69311.

It is an arithmetic number, because the mean of its divisors is an integer number (57278880).

Almost surely, 2^400021013 is an apocalyptic number.

It is an amenable number.

400021013 is a deficient number, since it is larger than the sum of its proper divisors (58210027).

400021013 is a wasteful number, since it uses less digits than its factorization.

400021013 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 133027.

The product of its (nonzero) digits is 24, while the sum is 11.

The square root of 400021013 is about 20000.5253181010. The cubic root of 400021013 is about 736.8192015945.

Adding to 400021013 its reverse (310120004), we get a palindrome (710141017).

The spelling of 400021013 in words is "four hundred million, twenty-one thousand, thirteen".