400644333031421 has 32 divisors (see below), whose sum is σ = 434735202249600. Its totient is φ = 368035875348480.

The previous prime is 400644333031399. The next prime is 400644333031451. The reversal of 400644333031421 is 124130333446004.

It is a cyclic number.

It is not a de Polignac number, because 400644333031421 - 2³⁸ = 400369455124477 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (400644333031451) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 166922525 + ... + 169305693.

It is an arithmetic number, because the mean of its divisors is an integer number (13585475070300).

Almost surely, 2^{400644333031421} is an apocalyptic number.

It is an amenable number.

400644333031421 is a deficient number, since it is larger than the sum of its proper divisors (34090869218179).

400644333031421 is a wasteful number, since it uses less digits than its factorization.

400644333031421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2385309.

The product of its (nonzero) digits is 248832, while the sum is 38.

Adding to 400644333031421 its reverse (124130333446004), we get a palindrome (524774666477425).

The spelling of 400644333031421 in words is "four hundred trillion, six hundred forty-four billion, three hundred thirty-three million, thirty-one thousand, four hundred twenty-one".