1221012077251 has 2 divisors, whose sum is σ = 1221012077252. Its totient is φ = 1221012077250.

The previous prime is 1221012077231. The next prime is 1221012077287. The reversal of 1221012077251 is 1527702101221.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1221012077251 - 2³¹ = 1218864593603 is a prime.

It is not a weakly prime, because it can be changed into another prime (1221012077221) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 610506038625 + 610506038626.

It is an arithmetic number, because the mean of its divisors is an integer number (610506038626).

Almost surely, 2^{1221012077251} is an apocalyptic number.

1221012077251 is a deficient number, since it is larger than the sum of its proper divisors (1).

1221012077251 is an equidigital number, since it uses as much as digits as its factorization.

1221012077251 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3920, while the sum is 31.

Adding to 1221012077251 its reverse (1527702101221), we get a palindrome (2748714178472).

The spelling of 1221012077251 in words is "one trillion, two hundred twenty-one billion, twelve million, seventy-seven thousand, two hundred fifty-one".