644213620460011 has 8 divisors (see below), whose sum is σ = 736245088221440. Its totient is φ = 552182390336808.

The previous prime is 644213620459951. The next prime is 644213620460021. The reversal of 644213620460011 is 110064026312446.

It is a happy number.

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

It is not a de Polignac number, because 644213620460011 - 2²⁵ = 644213586905579 is a prime.

It is a super-2 number, since 2×644213620460011² (a number of 30 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (644213620460021) 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 7 ways as a sum of consecutive naturals, for example, 53562111 + ... + 64477336.

It is an arithmetic number, because the mean of its divisors is an integer number (92030636027680).

Almost surely, 2^{644213620460011} is an apocalyptic number.

644213620460011 is a deficient number, since it is larger than the sum of its proper divisors (92031467761429).

644213620460011 is a wasteful number, since it uses less digits than its factorization.

644213620460011 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 118819113.

The product of its (nonzero) digits is 165888, while the sum is 40.

Adding to 644213620460011 its reverse (110064026312446), we get a palindrome (754277646772457).

The spelling of 644213620460011 in words is "six hundred forty-four trillion, two hundred thirteen billion, six hundred twenty million, four hundred sixty thousand, eleven".