20121967646579 has 2 divisors, whose sum is σ = 20121967646580. Its totient is φ = 20121967646578.

The previous prime is 20121967646563. The next prime is 20121967646597. The reversal of 20121967646579 is 97564676912102.

Together with next prime (20121967646597) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20121967646579 - 2⁴ = 20121967646563 is a prime.

It is not a weakly prime, because it can be changed into another prime (20121967645579) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10060983823289 + 10060983823290.

It is an arithmetic number, because the mean of its divisors is an integer number (10060983823290).

Almost surely, 2^{20121967646579} is an apocalyptic number.

20121967646579 is a deficient number, since it is larger than the sum of its proper divisors (1).

20121967646579 is an equidigital number, since it uses as much as digits as its factorization.

20121967646579 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 68584320, while the sum is 65.

The spelling of 20121967646579 in words is "twenty trillion, one hundred twenty-one billion, nine hundred sixty-seven million, six hundred forty-six thousand, five hundred seventy-nine".