646515356013321 has 48 divisors (see below), whose sum is σ = 915964001426880. Its totient is φ = 405484570719360.

The previous prime is 646515356013277. The next prime is 646515356013347. The reversal of 646515356013321 is 123310653515646.

It is not a de Polignac number, because 646515356013321 - 2⁴³ = 637719262991113 is a prime.

It is a super-2 number, since 2×646515356013321² (a number of 30 digits) contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (646515356013221) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1473860895 + ... + 1474299483.

It is an arithmetic number, because the mean of its divisors is an integer number (19082583363060).

Almost surely, 2^{646515356013321} is an apocalyptic number.

646515356013321 is a gapful number since it is divisible by the number (61) formed by its first and last digit.

It is an amenable number.

646515356013321 is a deficient number, since it is larger than the sum of its proper divisors (269448645413559).

646515356013321 is a wasteful number, since it uses less digits than its factorization.

646515356013321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 453926 (or 453903 counting only the distinct ones).

The product of its (nonzero) digits is 5832000, while the sum is 51.

The spelling of 646515356013321 in words is "six hundred forty-six trillion, five hundred fifteen billion, three hundred fifty-six million, thirteen thousand, three hundred twenty-one".