646215514222351 has 4 divisors (see below), whose sum is σ = 649495796020632. Its totient is φ = 642935232424072.

The previous prime is 646215514222331. The next prime is 646215514222363. The reversal of 646215514222351 is 153222415512646.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 646215514222351 - 2⁵ = 646215514222319 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 646215514222295 and 646215514222304.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (646215514222331) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1640140898845 + ... + 1640140899238.

It is an arithmetic number, because the mean of its divisors is an integer number (162373949005158).

Almost surely, 2^{646215514222351} is an apocalyptic number.

646215514222351 is a deficient number, since it is larger than the sum of its proper divisors (3280281798281).

646215514222351 is a wasteful number, since it uses less digits than its factorization.

646215514222351 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3280281798280.

The product of its digits is 3456000, while the sum is 49.

Adding to 646215514222351 its reverse (153222415512646), we get a palindrome (799437929734997).

The spelling of 646215514222351 in words is "six hundred forty-six trillion, two hundred fifteen billion, five hundred fourteen million, two hundred twenty-two thousand, three hundred fifty-one".