661427250321 has 8 divisors (see below), whose sum is σ = 933779647584. Its totient is φ = 415013176640.

The previous prime is 661427250307. The next prime is 661427250331. The reversal of 661427250321 is 123052724166.

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

It is a cyclic number.

It is not a de Polignac number, because 661427250321 - 2⁶ = 661427250257 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 661427250321.

It is not an unprimeable number, because it can be changed into a prime (661427250331) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6484580835 + ... + 6484580936.

It is an arithmetic number, because the mean of its divisors is an integer number (116722455948).

Almost surely, 2^661427250321 is an apocalyptic number.

It is an amenable number.

661427250321 is a deficient number, since it is larger than the sum of its proper divisors (272352397263).

661427250321 is a wasteful number, since it uses less digits than its factorization.

661427250321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12969161791.

The product of its (nonzero) digits is 120960, while the sum is 39.

Adding to 661427250321 its reverse (123052724166), we get a palindrome (784479974487).

The spelling of 661427250321 in words is "six hundred sixty-one billion, four hundred twenty-seven million, two hundred fifty thousand, three hundred twenty-one".