6401036660421 has 8 divisors (see below), whose sum is σ = 9191232127840. Its totient is φ = 3939099483312.

The previous prime is 6401036660399. The next prime is 6401036660423. The reversal of 6401036660421 is 1240666301046.

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

It is not a de Polignac number, because 6401036660421 - 2⁶ = 6401036660357 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (39), and also a Moran number because the ratio is a prime number: 164129145139 = 6401036660421 / (6 + 4 + 0 + 1 + 0 + 3 + 6 + 6 + 6 + 0 + 4 + 2 + 1).

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 6401036660421.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6401036660423) 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, 82064572531 + ... + 82064572608.

It is an arithmetic number, because the mean of its divisors is an integer number (1148904015980).

Almost surely, 2^{6401036660421} is an apocalyptic number.

It is an amenable number.

6401036660421 is a deficient number, since it is larger than the sum of its proper divisors (2790195467419).

6401036660421 is a wasteful number, since it uses less digits than its factorization.

6401036660421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 164129145155.

The product of its (nonzero) digits is 124416, while the sum is 39.

The spelling of 6401036660421 in words is "six trillion, four hundred one billion, thirty-six million, six hundred sixty thousand, four hundred twenty-one".