1221000122651 has 2 divisors, whose sum is σ = 1221000122652. Its totient is φ = 1221000122650.

The previous prime is 1221000122603. The next prime is 1221000122701. The reversal of 1221000122651 is 1562210001221.

It is a weak prime.

It is an emirp because it is prime and its reverse (1562210001221) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1221000122651 is a prime.

It is not a weakly prime, because it can be changed into another prime (1221000121651) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 610500061325 + 610500061326.

It is an arithmetic number, because the mean of its divisors is an integer number (610500061326).

Almost surely, 2^{1221000122651} is an apocalyptic number.

1221000122651 is a deficient number, since it is larger than the sum of its proper divisors (1).

1221000122651 is an equidigital number, since it uses as much as digits as its factorization.

1221000122651 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 480, while the sum is 23.

Adding to 1221000122651 its reverse (1562210001221), we get a palindrome (2783210123872).

The spelling of 1221000122651 in words is "one trillion, two hundred twenty-one billion, one hundred twenty-two thousand, six hundred fifty-one".