321660420646 has 4 divisors (see below), whose sum is σ = 482490630972. Its totient is φ = 160830210322.

The previous prime is 321660420623. The next prime is 321660420677. The reversal of 321660420646 is 646024066123.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 646024066123 = 56383 ⋅11457781.

It is a junction number, because it is equal to n+sod(n) for n = 321660420599 and 321660420608.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80415105160 + ... + 80415105163.

It is an arithmetic number, because the mean of its divisors is an integer number (120622657743).

Almost surely, 2^321660420646 is an apocalyptic number.

321660420646 is a deficient number, since it is larger than the sum of its proper divisors (160830210326).

321660420646 is a wasteful number, since it uses less digits than its factorization.

321660420646 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 160830210325.

The product of its (nonzero) digits is 248832, while the sum is 40.

Adding to 321660420646 its reverse (646024066123), we get a palindrome (967684486769).

The spelling of 321660420646 in words is "three hundred twenty-one billion, six hundred sixty million, four hundred twenty thousand, six hundred forty-six".