400343231000021 has 16 divisors (see below), whose sum is σ = 415059722719488. Its totient is φ = 385862798553600.

The previous prime is 400343231000017. The next prime is 400343231000023. The reversal of 400343231000021 is 120000132343004.

It is not a de Polignac number, because 400343231000021 - 2² = 400343231000017 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (400343231000023) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 128871380 + ... + 131941346.

It is an arithmetic number, because the mean of its divisors is an integer number (25941232669968).

Almost surely, 2^{400343231000021} is an apocalyptic number.

400343231000021 is a gapful number since it is divisible by the number (41) formed by its first and last digit.

It is an amenable number.

400343231000021 is a deficient number, since it is larger than the sum of its proper divisors (14716491719467).

400343231000021 is a wasteful number, since it uses less digits than its factorization.

400343231000021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3108412.

The product of its (nonzero) digits is 1728, while the sum is 23.

Adding to 400343231000021 its reverse (120000132343004), we get a palindrome (520343363343025).

The spelling of 400343231000021 in words is "four hundred trillion, three hundred forty-three billion, two hundred thirty-one million, twenty-one", and thus it is an aban number.