400130021 has 8 divisors (see below), whose sum is σ = 402546144. Its totient is φ = 397721520.

The previous prime is 400129999. The next prime is 400130039. The reversal of 400130021 is 120031004.

It is a happy number.

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 400130021 - 2¹⁸ = 399867877 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 400129984 and 400130011.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (400130221) 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, 128930 + ... + 131996.

It is an arithmetic number, because the mean of its divisors is an integer number (50318268).

Almost surely, 2^400130021 is an apocalyptic number.

It is an amenable number.

400130021 is a deficient number, since it is larger than the sum of its proper divisors (2416123).

400130021 is a wasteful number, since it uses less digits than its factorization.

400130021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3811.

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

The square root of 400130021 is about 20003.2502608951. The cubic root of 400130021 is about 736.8861246562.

Adding to 400130021 its reverse (120031004), we get a palindrome (520161025).

The spelling of 400130021 in words is "four hundred million, one hundred thirty thousand, twenty-one".