646337691393 has 16 divisors (see below), whose sum is σ = 887095673856. Its totient is φ = 418403381760.

The previous prime is 646337691367. The next prime is 646337691397. The reversal of 646337691393 is 393196733646.

It is not a de Polignac number, because 646337691393 - 2¹⁸ = 646337429249 is a prime.

It is a super-2 number, since 2×646337691393² (a number of 24 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (646337691397) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 20938273 + ... + 20969118.

It is an arithmetic number, because the mean of its divisors is an integer number (55443479616).

Almost surely, 2^646337691393 is an apocalyptic number.

It is an amenable number.

646337691393 is a deficient number, since it is larger than the sum of its proper divisors (240757982463).

646337691393 is a wasteful number, since it uses less digits than its factorization.

646337691393 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41907544.

The product of its digits is 39680928, while the sum is 60.

The spelling of 646337691393 in words is "six hundred forty-six billion, three hundred thirty-seven million, six hundred ninety-one thousand, three hundred ninety-three".