400343343320421 has 48 divisors (see below), whose sum is σ = 619456045506480. Its totient is φ = 248258445557760.

The previous prime is 400343343320377. The next prime is 400343343320483. The reversal of 400343343320421 is 124023343343004.

400343343320421 is a `hidden beast` number, since 40 + 0 + 34 + 334 + 33 + 204 + 21 = 666.

It can be written as a sum of positive squares in 8 ways, for example, as 25730763502500 + 374612579817921 = 5072550^2 + 19354911^2 .

It is not a de Polignac number, because 400343343320421 - 2¹⁰ = 400343343319397 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (400343343320021) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 22623871 + ... + 36228803.

It is an arithmetic number, because the mean of its divisors is an integer number (12905334281385).

Almost surely, 2^{400343343320421} is an apocalyptic number.

It is an amenable number.

400343343320421 is a deficient number, since it is larger than the sum of its proper divisors (219112702186059).

400343343320421 is a wasteful number, since it uses less digits than its factorization.

400343343320421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13607206 (or 13607203 counting only the distinct ones).

The product of its (nonzero) digits is 248832, while the sum is 36.

Adding to 400343343320421 its reverse (124023343343004), we get a palindrome (524366686663425).

The spelling of 400343343320421 in words is "four hundred trillion, three hundred forty-three billion, three hundred forty-three million, three hundred twenty thousand, four hundred twenty-one".